CN104496918B

CN104496918B - Pyrazines derivatives and application thereof

Info

Publication number: CN104496918B
Application number: CN201410758789.7A
Authority: CN
Inventors: 任青云; 刘辛昌; 唐昌华; 张健存; 张英俊
Original assignee: Guangdong HEC Pharmaceutical
Current assignee: Guangdong HEC Pharmaceutical
Priority date: 2014-12-10
Filing date: 2014-12-10
Publication date: 2016-08-24
Anticipated expiration: 2034-12-10
Also published as: CN104496918A

Abstract

The present invention relates to a class pyrazines derivatives, or its stereoisomer, geometric isomer, tautomer, nitrogen oxides, hydrate, solvate, metabolite, pharmaceutically acceptable salt or prodrug.The invention still further relates to pyrazines derivatives or its stereoisomer, geometric isomer, tautomer, nitrogen oxides, hydrate, solvate, metabolite, pharmaceutically acceptable salt or the prodrug purposes as medicine, the especially application in preparation antiviral drugs.

Description

Pyrazine derivatives and uses thereof

Technical Field

The invention relates to a pyrazine derivative, a preparation method thereof and application thereof in preparing antiviral drugs, in particular to application in preparing drugs for preventing and treating diseases related to influenza viruses. The invention also relates to a pharmaceutical composition containing the compounds and application of the pharmaceutical composition in preventing and treating diseases related to influenza viruses.

Background

Influenza (influenza for short) is acute respiratory infection caused by influenza virus, and is also a disease with strong infectivity and high transmission speed. It is transmitted primarily by airborne droplets, human-to-human contact, or contact with contaminated items. Typical clinical symptoms are: acute high fever, general pain, marked weakness and mild respiratory symptoms. Generally, the autumn and winter season is the high-incidence period of the disease, and the complications and death phenomena caused by the disease are very serious.

In recent years, research on influenza virus resistant drugs has been greatly advanced, and different influenza virus resistant drugs have different effects in preventing and treating influenza. M2 ion channel protein inhibitors (such as amantadine and rimantadine) are the earliest drugs for clinical treatment of influenza on the market, but have limitations of increased drug-resistant strain ratio and primary efficacy against influenza B virus. The successful development of neuraminidase inhibitors is a breakthrough progress in the research of herbal medicines for resisting influenza viruses at present, and has inhibitory activity on influenza A and B viruses, for example, oseltamivir is the first medicine for preventing and treating avian influenza and human influenza epidemics, however, in recent years, researchers all over the world continuously discover H1N1, H5N1, H3N2 and influenza B viruses which have resistance to oseltamivir. Other anti-influenza virus drugs have better inhibitory effect on viruses and antiviral application prospect according to literature reports, but further demonstration is often needed.

Because the wide clinical application of the existing drugs causes the influenza virus to have variation, the drugs have different degrees of resistance to the drugs. Therefore, the development of novel anti-influenza virus drugs is not slow.

The present invention provides a novel antiviral drug which has preventive and therapeutic effects on influenza virus-related diseases.

Disclosure of Invention

The invention relates to a pyrazine derivative, a preparation method thereof and application thereof in preparing antiviral drugs. The compound or the pharmaceutical composition containing the compound has certain anti-influenza virus activity, and particularly has better effect on preventing and treating influenza virus.

In one aspect, the invention relates to a compound that is a structural formula shown in formula (I) or a stereoisomer, geometric isomer, tautomer, nitrogen oxide, hydrate, solvate, metabolite, pharmaceutically acceptable salt or prodrug of the structure shown in formula (I),

wherein,

x is halogen; and R¹Is hydroxyalkyl.

In some embodiments, X is F, Cl, Br, or I; and

R¹is C₁-C₆A hydroxyalkyl group.

In some embodiments, R¹Is 3-hydroxypropyl, 2-hydroxypropyl, 1-hydroxypropyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1, 3-dihydroxypropan-2-yl, hydroxybutyl, 2, 4-dihydroxybutyl, hydroxypentyl or hydroxyhexyl.

In some embodiments, the compounds of the invention are stereoisomers, geometric isomers, tautomers, nitrogen oxides, hydrates, solvates, metabolites, pharmaceutically acceptable salts, or prodrugs of the structures of formula (II) or of the structures of formula (II),

wherein R is¹Is C₁-C₆A hydroxyalkyl group.

In some embodiments, R¹Is 3-hydroxypropyl, 2-hydroxypropyl, 1-hydroxypropyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1, 3-dihydroxypropan-2-yl, 1, 3-dihydroxy-2- (hydroxymethyl)-propan-2-yl, hydroxybutyl, 2, 4-dihydroxybutyl, hydroxypentyl or hydroxyhexyl.

In other embodiments, the invention relates to compounds of one of the structures,

or a stereoisomer, geometric isomer, tautomer, nitrogen oxide, hydrate, solvate, metabolite, pharmaceutically acceptable salt, or prodrug of the structure shown.

In another aspect, the invention relates to a pharmaceutical composition comprising a compound of any of the present invention, and a pharmaceutically acceptable carrier, excipient, diluent, adjuvant, vehicle, or combination thereof.

In some embodiments, the pharmaceutical composition further comprises an additional anti-influenza virus drug, wherein the anti-influenza virus drug is peramivir, zanamivir, oseltamivir, nannimivir, faviravir, amantadine, rimantadine, ribavirin, stafurin, Ingavirin (Ingavirin), GR-217029, or a combination thereof.

In another aspect, the invention relates to the use of any one of the compounds of the invention or any one of the pharmaceutical compositions in the manufacture of a medicament for the prevention, treatment or alleviation of an influenza virus related disease in a patient.

Another aspect of the invention relates to methods for the preparation, isolation and purification of compounds encompassed by formula (I).

The invention also comprises the use of a compound of the invention, and stereoisomers, geometric isomers, tautomers, nitrogen oxides, hydrates, solvates, metabolites thereof, pharmaceutically acceptable salts or prodrugs thereof, in the manufacture of a medicament effective in inhibiting influenza virus. The compounds of the invention are also useful in the manufacture of a medicament for the alleviation, prevention, control or treatment of influenza virus infection in a patient. The present invention encompasses pharmaceutical compositions comprising a therapeutically effective amount of a compound represented by formula (I) in combination with at least one pharmaceutically acceptable carrier, adjuvant or diluent.

The invention also encompasses a method of treating a disease that is susceptible to or susceptible to an influenza virus, comprising treating a patient with a therapeutically effective amount of a compound represented by formula (I).

Unless otherwise indicated, all stereoisomers, geometric isomers, tautomers, nitroxides, hydrates, solvates, metabolites, salts and pharmaceutically acceptable prodrugs of the compounds of the invention are within the scope of the present invention.

In particular, the salts are pharmaceutically acceptable salts. The term "pharmaceutically acceptable" includes substances or compositions which must be compatible with chemical or toxicological considerations, in connection with the other components which make up the formulation and the mammal being treated.

Salts of the compounds of the present invention also include, but are not necessarily pharmaceutically acceptable salts of intermediates used in the preparation or purification of the compounds of formula (I) or isolated enantiomers of the compounds of formula (I).

If the compounds of the invention are basic, the desired salts may be prepared by any suitable method provided in the literature, for example, using inorganic acids such as hydrochloric, hydrobromic, sulfuric, metaphosphoric, nitric and phosphoric acids, and the like. Or using organic acids, lactic acid, lactobionic acid, trifluoroacetic acid, acetic acid, maleic acid, succinic acid, mandelic acid, fumaric acid, malonic acid, pyruvic acid, malic acid, 2-hydroxypropionic acid, citric acid, oxalic acid, glycolic acid and salicylic acid; pyranonic acids, such as glucuronic acid and galacturonic acid; alpha-hydroxy acids such as citric acid and tartaric acid; amino acids such as aspartic acid and glutamic acid; aromatic acids such as benzoic acid and cinnamic acid; sulfonic acids such as p-toluenesulfonic acid, benzenesulfonic acid, methanesulfonic acid, ethanesulfonic acid, isethionic acid, trifluoromethanesulfonic acid, and the like, or combinations thereof.

If the compounds of the invention are acidic, the desired salts can be prepared by suitable methods, e.g., using inorganic or organic bases, such as ammonia (primary, secondary, tertiary), alkali metal hydroxides, ammonium, N⁺(R¹⁴)₄Salts and alkaline earth metal hydroxides, and the like. Suitable salts include, but are not limited to, organic salts derived from amino acids, such as glycine and arginine, ammonia, such as primary, secondary and tertiary, N⁺(R¹⁴)₄Salts, e.g. R¹⁴Is H, C_1-4Alkyl radical, C_6-10Aryl radical, C_6-10Aryl radical C_1-4Alkyl, etc., and cyclic amines such as piperidine, morpholine, piperazine, etc., and inorganic salts derived from sodium, calcium, potassium, magnesium, manganese, iron, copper, zinc, aluminum, and lithium. Also included are suitable, non-toxic ammonium, quaternary ammonium salts and amine cations resistant to formation of counterions, e.g., halides, hydroxides, carboxylates, sulfates, phosphates, nitrates, C_1-8Sulfonates and aromatic sulfonates.

Detailed description of the invention

Definitions and general terms

Reference will now be made in detail to certain embodiments of the invention, examples of which are illustrated by the accompanying structural and chemical formulas. The invention is intended to cover alternatives, modifications and equivalents, which may be included within the scope of the invention as defined by the appended claims. Those skilled in the art will recognize that many methods and materials similar or equivalent to those described herein can be used in the practice of the present invention. The present invention is in no way limited to the methods and materials described herein. In the event that one or more of the incorporated documents, patents, and similar materials differ or contradict this application (including but not limited to defined terminology, application of terminology, described techniques, and the like), this application controls.

It will be further appreciated that certain features of the invention, which are, for clarity, described in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features of the invention which are, for brevity, described in the context of a single embodiment, may also be provided separately or in any suitable subcombination.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. All patents and publications referred to herein are incorporated by reference in their entirety.

The following definitions as used herein should be applied, unless otherwise indicated. For the purposes of the present invention, the chemical elements are in accordance with the CAS version of the periodic Table of the elements, and the handbook of chemistry and Physics, 75 th edition, 1994. In addition, general principles of Organic Chemistry can be found in the descriptions of "Organic Chemistry", Thomas Sorrell, University Science Books, Sausaltito: 1999, and "March's Advanced Organic Chemistry" by Michael B.Smith and Jerry March, John Wiley & Sons, New York:2007, the entire contents of which are incorporated herein by reference.

The articles "a," "an," and "the" as used herein are intended to include "at least one" or "one or more" unless otherwise indicated or clearly contradicted by context. Thus, as used herein, the articles refer to articles of one or more than one (i.e., at least one) object. For example, "a component" refers to one or more components, i.e., there may be more than one component contemplated for use or use in embodiments of the described embodiments.

The term "subject" as used herein refers to an animal. Typically the animal is a mammal. Subjects, e.g., also primates (e.g., humans, males or females), cows, sheep, goats, horses, dogs, cats, rabbits, rats, mice, fish, birds, etc. In certain embodiments, the subject is a primate. In other embodiments, the subject is a human.

The term "patient" as used herein refers to humans (including adults and children) or other animals. In some embodiments, "patient" refers to a human.

The term "comprising" is open-ended, i.e. includes the elements indicated in the present invention, but does not exclude other elements.

The stereochemical definitions and rules used in the present invention generally follow the general definitions of S.P. Parker, Ed., McGraw-Hilldictionary of Chemical Terms (1984) McGraw-Hill Book Company, New York; andEliel, E.and Wilen, S., "Stereochemistry of Organic Compounds", John Wiley & Sons, Inc., New York,1994.

Many organic compounds exist in an optically active form, i.e., they have the ability to rotate the plane of plane polarized light. In describing optically active compounds, the prefixes D and L or R and S are used to denote the absolute configuration of a molecule with respect to one or more of its chiral centers. The prefixes d and l or (+) and (-) are the symbols used to specify the rotation of plane polarized light by the compound, where (-) or l indicates that the compound is left-handed. Compounds prefixed with (+) or d are dextrorotatory. A particular stereoisomer is an enantiomer and a mixture of such isomers is referred to as an enantiomeric mixture. A50: 50 mixture of enantiomers is referred to as a racemic mixture or racemate, which may occur when there is no stereoselectivity or stereospecificity in the chemical reaction or process.

Any asymmetric atom (e.g., carbon, etc.) of a compound disclosed herein can exist in racemic or enantiomerically enriched forms, such as the (R) -, (S) -or (R, S) -configuration. In certain embodiments, each asymmetric atom has at least 50% enantiomeric excess, at least 60% enantiomeric excess, at least 70% enantiomeric excess, at least 80% enantiomeric excess, at least 90% enantiomeric excess, at least 95% enantiomeric excess, or at least 99% enantiomeric excess in the (R) -or (S) -configuration.

Depending on the choice of starting materials and methods, the compounds of the invention may exist as one of the possible isomers or as mixtures thereof, for example as racemates and diastereomeric mixtures (depending on the number of asymmetric carbon atoms). Optically active (R) -or (S) -isomers can be prepared using chiral synthons or chiral reagents, or resolved using conventional techniques. If the compound contains a double bond, the substituents may be in the E or Z configuration; if the compound contains a disubstituted cycloalkyl group, the substituents of the cycloalkyl group may have cis or trans configuration.

Any resulting mixture of stereoisomers may be separated into pure or substantially pure geometric isomers, enantiomers, diastereomers, depending on differences in the physicochemical properties of the components, for example, by chromatography and/or fractional crystallization.

The racemates of any of the resulting end products or intermediates can be resolved into the optical enantiomers by known methods using methods familiar to those skilled in the art, e.g., by separation of the diastereomeric salts obtained. The racemic product can also be separated by chiral chromatography, e.g., High Performance Liquid Chromatography (HPLC) using a chiral adsorbent. In particular, Enantiomers can be prepared by asymmetric synthesis, for example, see Jacques, et al, Enantiomers, racemases and solutions (Wiley Interscience, New York, 1981); principles of Asymmetric Synthesis (2)^ndEd.Robert E.Gawley,Jeffrey Aubé,Elsevier,Oxford,UK,2012)；Eliel,E.L.Stereochemistry of Carbon Compounds(McGraw-Hill,NY,1962)；Wilen,S.H.Tablesof Resolving Agents and Optical Resolutions p.268(E.L.Eliel,Ed.,Univ.of NotreDame Press,Notre Dame,IN 1972)；Chiral Separation Techniques:A PracticalApproach(Subramanian,G.Ed.,Wiley-VCH Verlag GmbH&Co.KGaA,Weinheim,Germany,2007)。

In the various parts of this specification, substituents of the disclosed compounds are disclosed in terms of group type or range. It is specifically intended that the invention includes each and every independent subcombination of the various members of these groups and ranges. For example, the term "C_1-C₆Alkyl "means in particular independently disclosed methyl, ethyl, C₃Alkyl radical, C₄Alkyl radical, C₅Alkyl and C₆An alkyl group.

In each of the parts of the invention, linking substituents are described. Where the structure clearly requires a linking group, the markush variables listed for that group are understood to be linking groups. For example, if the structure requires a linking group and the markush group definition for the variable recites "alkyl" or "aryl," it is understood that the "alkyl" or "aryl" represents an attached alkylene group or arylene group, respectively.

The term "alkyl" or "alkyl group" as used herein, denotes a saturated, straight or branched chain monovalent hydrocarbon radical containing from 1 to 20 carbon atoms, wherein the alkyl group may be optionally substituted with one or more substituents as described herein. In some embodiments, the alkyl group contains 1 to 10 carbon atoms; in another embodiment, the alkyl group contains 1 to 6 carbon atoms; in yet another embodiment, the alkyl group contains 1 to 4 carbon atoms; in yet another embodiment, the alkyl group contains 1 to 3 carbon atoms. Examples of alkyl groups include, but are not limited to, methyl (Me, -CH)₃) Ethyl (Et-CH)₂CH₃) N-propyl (n-Pr, -CH)₂CH₂CH₃) Isopropyl (i-Pr, -CH (CH)₃)₂) N-butyl (n-Bu, -CH)₂CH₂CH₂CH₃) Isobutyl (i-Bu, -CH)₂CH(CH₃)₂) Sec-butyl (s-Bu, -CH (CH)₃)CH₂CH₃) Tert-butyl (t-Bu, -C (CH)₃)₃) N-pentyl (-CH)₂CH₂CH₂CH₂CH₃) 2-pentyl (-CH (CH)₃)CH₂CH₂CH₃) 3-pentyl (-CH (CH)₂CH₃)₂) 2-methyl-2-butyl (-C (CH)₃)₂CH₂CH₃) 3-methyl-2-butyl (-CH (CH)₃)CH(CH₃)₂) 3-methyl-1-butyl (-CH)₂CH₂CH(CH₃)₂) 2-methyl-1-butyl (-CH)₂CH(CH₃)CH₂CH₃) 2-ethyl-1-butyl (-CH)₂CH(CH₂CH₃)CH₂CH₃) N-hexyl (-CH)₂CH₂CH₂CH₂CH₂CH₃) 2-hexyl (-CH (CH)₃)CH₂CH₂CH₂CH₃) 3-hexyl (-CH (CH)₂CH₃)(CH₂CH₂CH₃) 2-methyl-2-pentyl (-C (CH))₃)₂CH₂CH₂CH₃) 3-methyl-2-pentyl (-CH (CH)₃)CH(CH₃)CH₂CH₃) 4-methyl-2-pentyl (-CH (CH)₃)CH₂CH(CH₃)₂) 3-methyl-3-pentyl (-C (CH)₃)(CH₂CH₃)₂) 2-methyl-3-pentyl (-CH (CH)₂CH₃)CH(CH₃)₂) 2, 3-dimethyl-2-butyl (-C (CH)₃)₂CH(CH₃)₂) 3, 3-dimethyl-2-butyl (-CH (CH)₃)C(CH₃)₃) N-heptyl, n-octyl, and the like.

The term "halogen" refers to fluorine (F), chlorine (Cl), bromine (Br) or iodine (I).

The term "hydroxy" refers to "-OH".

The term "hydroxyalkyl" or "hydroxyalkyl" denotes an alkyl group substituted with one or more hydroxyl groups, wherein the hydroxyl group and the alkyl group have the meaning as described herein. In some embodiments, the hydroxyalkyl group contains 1 to 6 carbon atoms; in another embodiment, the hydroxyl group contains 1 to 4 carbon atoms; in yet another embodiment, the hydroxyl group contains 1 to 3 carbon atoms. Examples include, but are not limited to, 3-hydroxypropyl, 2-hydroxypropyl, 1-hydroxypropyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1, 3-dihydroxyprop-2-yl, 1, 3-dihydroxyprop-2- (hydroxymethyl) -prop-2-yl, hydroxybutyl, 2, 4-dihydroxybutyl, hydroxypentyl or hydroxyhexyl, and the like.

Unless otherwise indicated, the structural formulae depicted herein include all isomeric forms (e.g., enantiomeric, diastereomeric, and geometric (or conformational) isomers): such as the R, S configuration containing an asymmetric center, the (Z), (E) isomers of the double bond, and the conformational isomers of (Z), (E). Thus, individual stereochemical isomers of the compounds of the present invention or mixtures of enantiomers, diastereomers, or geometric isomers (or conformers) thereof are within the scope of the present invention.

Unless otherwise indicated, the structural formulae depicted herein and the compounds depicted herein include all isomeric forms (e.g., enantiomeric, diastereomeric, geometric or conformational isomers), nitroxides, hydrates, solvates, metabolites, pharmaceutically acceptable salts and prodrugs. Thus, compounds that are individual stereochemically isomeric forms, enantiomeric forms, diastereomeric forms, geometric forms, conformational forms, nitrogen oxides, hydrates, solvates, metabolites, pharmaceutically acceptable salts and prodrugs of the compounds of the present invention are also within the scope of the present invention. In addition, unless otherwise indicated, the structural formulae of the compounds described herein include isotopically enriched concentrations of one or more different atoms.

The term "protecting group" or "Pg" refers to a substituent that when reacted with other functional groups, is typically used to block or protect a particular functionality. For example, "amino protecting group" means a substituent attached to an amino group to block or protect the functionality of the amino group in a compound, and suitable amino protecting groups include acetyl, trifluoroacetyl, t-butoxycarbonyl (BOC ), benzyloxycarbonyl (CBZ ) and 9-fluorenylmethyleneoxycarbonyl (Fmoc). Similarly, "hydroxyl protecting group" refers to the functionality of a substituent of a hydroxyl group to block or protect the hydroxyl group, and suitable protecting groups include acetyl and silyl groups. "carboxy protecting group" refers to the functionality of a substituent of a carboxy group to block or protect the carboxy group, and typical carboxy protecting groups include-CH₂CH₂SO₂Ph, cyanoethyl, 2- (trimethylsilyl) ethyl, 2- (trimethylsilyl) ethoxymethyl, 2- (p-toluenesulfonyl) ethyl2- (p-nitrobenzenesulfonyl) ethyl, 2- (diphenylphosphino) ethyl, nitroethyl, and the like. General descriptions of protecting groups can be found in the literature: greene, Protective Groups in Organic Synthesis, John Wiley&Sons,New York,1991；and P.J.Kocienski,Protecting Groups,Thieme,Stuttgart,2005。

The term "prodrug", as used herein, represents a compound that is converted in vivo to a compound of formula (I). Such conversion is effected by hydrolysis of the prodrug in the blood or by enzymatic conversion to the parent structure in the blood or tissue. The prodrug compound of the invention can be ester, and in the prior invention, the ester can be used as the prodrug and comprises phenyl ester and aliphatic (C)_1-24) Esters, acyloxymethyl esters, carbonates, carbamates and amino acid esters. For example, a compound of the present invention contains a hydroxy group, i.e., it can be acylated to provide the compound in prodrug form. Other prodrug forms include phosphate esters, such as those obtained by phosphorylation of a hydroxyl group on the parent. For a complete discussion of prodrugs, reference may be made to the following: T.Higuchi and V.Stella, Pro-drugs as Novel delivery systems, Vol.14 of the A.C.S.Sympossium Series, Edward B.Roche, ed., Bioredeployers in Drug designs, American Pharmaceutical Association and PergammonPress, 1987, J.Rautio et al, Prodrugs in Design and Clinical Applications, Nature Review Drug Discovery,2008,7,255 and 270, and S.J.Herer et al, Prodrugs of pharmaceuticals and pharmaceuticals, Journal of chemical Chemistry,2008,51,2328 and 2345.

"metabolite" refers to the product of a particular compound or salt thereof obtained by metabolism in vivo. Metabolites of a compound can be identified by techniques well known in the art, and its activity can be characterized by assay methods as described herein. Such products may be obtained by administering the compound by oxidation, reduction, hydrolysis, amidation, deamidation, esterification, defatting, enzymatic cleavage, and the like. Accordingly, the present invention includes metabolites of compounds, including metabolites produced by contacting a compound of the present invention with a mammal for a sufficient period of time.

The definition and convention of stereochemistry in the present invention is generally used with reference to the following documents: S.P. Parker, Ed., McGraw-Hill Dictionary of Chemical Terms (1984) McGraw-Hill Book Company, New York; and Eliel, E.and Wilen, S., "stereoschemistry of Organic Compounds", John Wiley & Sons, Inc., New York,1994. All stereoisomeric forms of the compounds of the present invention, including, but in no way limited to, diastereomers, enantiomers, atropisomers, and mixtures thereof, such as racemic mixtures, form part of the present invention. Many organic compounds exist in optically active form, i.e., they have the ability to rotate the plane of plane polarized light. In describing optically active compounds, the prefix D, L or R, S is used to indicate the absolute configuration of the chiral center of the molecule. The prefixes d, l or (+), (-) are used to designate the sign of the rotation of plane polarized light of the compound, with (-) or l indicating that the compound is left-handed and the prefix (+) or d indicating that the compound is right-handed. The chemical structures of these stereoisomers are identical, but their stereo structures are different. A particular stereoisomer may be an enantiomer, and a mixture of isomers is commonly referred to as a mixture of enantiomers. 50:50 is called a racemic mixture or racemate, which may result in no stereoselectivity or stereospecificity during the chemical reaction. The terms "racemic mixture" and "racemate" refer to a mixture of two enantiomers in equimolar amounts, lacking optical activity.

"stereoisomers" refers to compounds having the same chemical structure but differing in the arrangement of atoms or groups in space. Stereoisomers include enantiomers, diastereomers, conformers (rotamers), geometric isomers (cis/trans), atropisomers, and the like.

The term "tautomer" or "tautomeric form" means that isomers of structures of different energies may be interconverted through a low energy barrier. For example, proton tautomers (i.e., prototropic tautomers) include tautomers that move through protons, such as keto-enol and imine-enamine isomerizations. Valence (valence) tautomers include tautomers that recombine into bond electrons.

"chiral" is a molecule having the property of not overlapping its mirror image; and "achiral" refers to a molecule that can overlap with its mirror image.

"enantiomer" refers to two isomers of a compound that are not overlapping but are in mirror image relationship to each other.

"diastereomer" refers to a stereoisomer having two or more chiral centers and whose molecules are not mirror images of each other. Diastereomers have different physical properties, such as melting points, boiling points, spectral properties, and reactivities. Mixtures of diastereomers may be separated by high resolution analytical procedures such as electrophoresis and chromatography, e.g., HPLC.

As used herein, "pharmaceutically acceptable salts" refer to organic and inorganic salts of the compounds of the present invention. Pharmaceutically acceptable salts are well known in the art, as are: berge et al, descriptive acceptable salts in detail in J. pharmaceutical Sciences,1977,66:1-19. Pharmaceutically acceptable non-toxic acid salts include, but are not limited to, salts of inorganic acids formed by reaction with amino groups such as hydrochlorides, hydrobromides, phosphates, sulfates, perchlorates, and salts of organic acids such as acetates, oxalates, maleates, tartrates, citrates, succinates, malonates, or those obtained by other methods described in the literature above, such as ion exchange. Other pharmaceutically acceptable salts include adipates, alginates, ascorbates, aspartates, benzenesulfonates, benzoates, bisulfates, borates, butyrates, camphorates, camphorsulfonates, cyclopentylpropionates, digluconates, dodecylsulfates, ethanesulfonates, formates, fumaric acidSalts, glucoheptonate, glycerophosphate, gluconate, hemisulfate, heptanoate, hexanoate, hydroiodide, 2-hydroxy-ethanesulfonate, lactobionate, lactate, laurate, lauryl sulfate, malate, malonate, methanesulfonate, 2-naphthalenesulfonate, nicotinate, nitrate, oleate, palmitate, pamoate, pectate, persulfate, 3-phenylpropionate, picrate, pivalate, propionate, stearate, thiocyanate, p-toluenesulfonate, undecanoate, valerate, and the like. Salts obtained with appropriate bases include alkali metals, alkaline earth metals, ammonium and N⁺(C_1-4Alkyl radical)₄A salt. The present invention also contemplates quaternary ammonium salts formed from compounds containing groups of N. Water-soluble or oil-soluble or dispersion products can be obtained by quaternization. Alkali or alkaline earth metal salts include sodium, lithium, potassium, calcium, magnesium, and the like. Pharmaceutically acceptable salts further include suitable, non-toxic ammonium, quaternary ammonium salts and amine cations resistant to formation of counterions, such as halides, hydroxides, carboxylates, sulfates, phosphates, nitrates, C_1-8Sulfonates and aromatic sulfonates.

The "hydrate" of the present invention means an association of solvent molecules with water.

"nitroxide" in the context of the present invention means that when a compound contains several amine functional groups, 1 or more than 1 nitrogen atom can be oxidized to form an N-oxide. Specific examples of N-oxides are N-oxides of tertiary amines or N-oxides of nitrogen-containing heterocyclic nitrogen atoms. The corresponding amines can be treated with an oxidizing agent such as hydrogen peroxide or a peracid (e.g., peroxycarboxylic acid) to form the N-oxide (see Advanced Organic Chemistry, Wiley Interscience, 4 th edition, Jerry March, pages). In particular, the N-oxide may be prepared by the method of L.W.Deady (Syn.Comm.1977,7,509-514) in which an amine compound is reacted with m-chloroperoxybenzoic acid (MCPBA), for example, in an inert solvent such as dichloromethane.

"solvate" of the present invention refers to an association of one or more solvent molecules with a compound of the present invention. Solvents that form solvates include, but are not limited to, water, isopropanol, ethanol, methanol, dimethyl sulfoxide, ethyl acetate, acetic acid, and aminoethanol. The term "hydrate" refers to an association of solvent molecules that is water.

The term "treating" or "treatment" as used herein refers, in some embodiments, to ameliorating a disease or disorder (i.e., slowing or arresting or reducing the development of the disease or at least one clinical symptom thereof). In other embodiments, "treating" or "treatment" refers to moderating or improving at least one physical parameter, including physical parameters that may not be perceived by the patient. In other embodiments, "treating" or "treatment" refers to modulating the disease or disorder, either physically (e.g., stabilizing a perceptible symptom) or physiologically (e.g., stabilizing a parameter of the body), or both. In other embodiments, "treating" or "treatment" refers to preventing or delaying the onset, occurrence, or worsening of a disease or disorder.

Any formulae given herein are also intended to represent the non-isotopically enriched forms as well as the isotopically enriched forms of these compounds. Isotopically enriched compounds have the structure depicted by the formulae given herein, except that one or more atoms are replaced by an atom having a selected atomic mass or mass number. Exemplary isotopes that can be incorporated into compounds of the invention include isotopes of hydrogen, carbon, nitrogen, oxygen, phosphorus, sulfur, fluorine and chlorine, such as²H，³H，¹¹C，¹³C，¹⁴C，¹⁵N，¹⁷O，¹⁸O，¹⁸F，³¹P，³²P，³⁵S，³⁶Cl and¹²⁵I。

in another aspect, the compounds of the invention include isotopically enriched compounds as defined herein, e.g. wherein a radioisotope, e.g. is present³H，¹⁴C and¹⁸those compounds of F, or in which a non-radioactive isotope is present, e.g.²H and¹³C. the isotopically enriched compounds can be used for metabolic studies (use)¹⁴C) Reaction kinetics study (1)Using e.g.²H or³H) Detection or imaging techniques such as Positron Emission Tomography (PET) or Single Photon Emission Computed Tomography (SPECT) including drug or substrate tissue distribution determination, or may be used in radiotherapy of a patient.¹⁸F-enriched compounds are particularly desirable for PET or SPECT studies. Isotopically enriched compounds of formula (I) can be prepared by conventional techniques known to those skilled in the art or by the procedures and examples described in the present specification using a suitable isotopically labelled reagent in place of the original used unlabelled reagent.

In another aspect, the invention relates to intermediates for the preparation of compounds encompassed by formula (I).

In another aspect, the invention relates to methods for the preparation, isolation and purification of compounds encompassed by formula (I).

In another aspect, the present invention provides a pharmaceutical composition comprising a compound of the present invention, a pharmaceutically acceptable carrier, excipient, diluent, adjuvant, vehicle, or combination thereof. In some embodiments, the pharmaceutical composition may be in a liquid, solid, semi-solid, gel, or spray dosage form.

In addition, heavier isotopes are, in particular, deuterium (i.e.,²substitution of H or D) may provide certain therapeutic advantages resulting from greater metabolic stability. For example, increased in vivo half-life or decreased dosage requirements or improved therapeutic index. It is to be understood that deuterium in the present invention is considered as a substituent of the compound of formula (I). The concentration of such heavier isotopes, particularly deuterium, can be defined by isotopic enrichment factors. The term "isotopic enrichment factor" as used herein refers to the ratio between the isotopic and natural abundance of a given isotope. If a substituent of a compound of the invention is designated as deuterium, the compound has, for each designated deuterium atom, at least 3500 (52.5% deuterium incorporation at each designated deuterium atom), at least 4000 (60% deuterium incorporation), at least 4500 (67.5% deuterium incorporation), at least 5000 (75% deuterium incorporation), at least 5500 (82.5% deuterium incorporation), at least 5500Incorporation), at least 6000 (90% deuterium incorporation), at least 6333.3 (95% deuterium incorporation), at least 6466.7 (97% deuterium incorporation), at least 6600 (99% deuterium incorporation), or at least 6633.3 (99.5% deuterium incorporation). Pharmaceutically acceptable solvates of the invention include those in which the crystallization solvent may be isotopically substituted, e.g. D₂O, acetone-d₆、DMSO-d₆Those solvates of (a).

Compounds of the invention and pharmaceutical compositions, formulations and administrations thereof

The pharmaceutical composition comprises any one of the compounds of the present invention. The pharmaceutical composition may further comprise a pharmaceutically acceptable carrier, excipient, diluent, adjuvant, vehicle, or combination thereof.

The pharmaceutical composition further comprises an anti-influenza virus drug. The anti-influenza virus agent may be any other known agent for anti-influenza than the compound of the present invention. For example, it may be peramivir, zanamivir, oseltamivir, nannimivir, favipiravir, amantadine, abidol, ribavirin, stafurin, Ingavirin (Ingavirin), GR-217029, or a combination thereof.

When useful in therapy, a therapeutically effective amount of a compound of the present invention, particularly a compound of formula (I) and pharmaceutically acceptable salts thereof, may be administered as the raw chemical or as the active ingredient of a pharmaceutical composition. Accordingly, the present disclosure also provides pharmaceutical compositions comprising a therapeutically effective amount of a compound of the present invention, particularly a compound of formula (I) or a pharmaceutically acceptable salt thereof, and one or more pharmaceutically acceptable carriers, diluents or excipients. The term "therapeutically effective amount" as used herein refers to the total amount of each active component sufficient to show meaningful patient benefit (e.g., reduction in viral load). When the active ingredient alone is used for separate administration, the term refers only to that ingredient. When used in combination, the term refers to the combined amounts of the active ingredients that, when combined, administered sequentially or simultaneously, result in a therapeutic effect. The compounds of the invention, especially the compounds of formula (I) and pharmaceutically acceptable salts thereof, are as described above. The carrier, diluent or excipient must be acceptable in the sense of being compatible with the other ingredients of the formulation and not deleterious to the recipient thereof. According to another aspect of the present disclosure there is also provided a process for the preparation of a pharmaceutical formulation which comprises mixing a compound of the present invention, especially a compound of formula (I) or a pharmaceutically acceptable salt thereof, with one or more pharmaceutically acceptable carriers, diluents or excipients. The term "pharmaceutically acceptable" as used herein refers to compounds, materials, compositions, and/or dosage forms which are, within the scope of sound medical judgment, suitable for use in contact with the tissues of patients without excessive toxicity, irritation, allergic response, or other problem or complication commensurate with a reasonable benefit/risk ratio, and which are effective for their intended use.

The pharmaceutical preparations may be in unit dosage form, each unit dosage containing a predetermined amount of the active ingredient. Dosage levels of the compounds of the present disclosure are between about 0.01 and about 250 mg/kg body weight/day, preferably between about 0.05 and about 100mg/kg body weight/day, often as a monotherapy for the prevention or treatment of influenza virus mediated diseases. The pharmaceutical compositions of the present disclosure may generally be administered from about 1 to about 5 times per day or as a continuous infusion. Such administration may be used as a long term or short term therapy. The amount of active ingredient mixed with a carrier material to prepare a single dosage form will vary depending on the disease to be treated, the severity of the disease, the time of administration, the route of administration, the rate of excretion of the compound used, the time of treatment and the age, sex, body weight and condition of the patient. Preferred unit dosage forms are those containing a daily or divided dose or suitable fraction thereof of the active ingredient described herein above. Treatment can be initiated with small doses, which are clearly below the optimal dose of the compound. Thereafter, the dosage is increased in smaller increments until the optimum effect is achieved in this case. In general, the compounds are most desirably administered at concentration levels that generally provide effective results in terms of antiviral efficacy without causing any harmful or toxic side effects.

When the compositions of the present disclosure comprise a combination of a compound of the present disclosure and one or more other therapeutic or prophylactic agents, the dosage level of the compound and the additional agent(s) will generally be from about 10% to about 150% of the normally administered dose, more preferably from about 10% to about 80% of the normally administered dose, in a monotherapy regimen. The pharmaceutical formulations are adapted for administration by any suitable route, for example by the oral (including buccal or sublingual), rectal, nasal, topical (including buccal, sublingual or transdermal), vaginal or parenteral (including subcutaneous, intradermal, intramuscular, intraarticular, intrasynovial, intrasternal, intrathecal, intralesional, intravenous or subdermal injection or infusion) route. Such formulations may be prepared by any method known in the art of pharmacy, for example by mixing the active ingredient with a carrier or excipient. Oral administration or injection administration is preferred.

Pharmaceutical formulations adapted for oral administration are provided in discrete units, such as capsules or tablets; powder or granules; solutions or suspensions in aqueous or non-aqueous liquids; edible foam or foam formulations (whip); or an oil-in-water emulsion or a water-in-oil emulsion.

For example, for oral administration in the form of a tablet or capsule, the active pharmaceutical ingredient may be mixed with a pharmaceutically acceptable oral, non-toxic inert carrier (e.g., ethanol, glycerol, water, etc.). Powders are prepared by pulverizing the compound to a suitable fine size and mixing with a pharmaceutically acceptable carrier (e.g., an edible sugar such as starch or mannitol) which is also pulverized. Flavoring, preservative, dispersing and coloring agents may also be present.

Capsules are prepared by preparing a powdered mixture as described above and filling into shaped gelatin shells. Glidants and lubricants (e.g., colloidal silicon dioxide, talc, magnesium stearate, calcium stearate, or solid polyethylene glycol) may be added to the powder mixture prior to the filling operation. Disintegrating or solubilizing agents (e.g., agar-agar, calcium carbonate or sodium carbonate) that will improve the availability of the drug when the capsule is taken can also be added.

In addition, if desired or necessary, suitable binders, lubricants, disintegrating agents and coloring agents can also be incorporated into the mixture. Suitable binders include starch, gelatin, natural sugars (e.g., glucose or beta-lactose), corn sweeteners, natural and synthetic gums (e.g., gum arabic, tragacanth or sodium alginate), carboxymethylcellulose, polyethylene glycol, and the like. Lubricants used in these dosage forms include sodium oleate, sodium chloride, and the like. Disintegrants include, but are not limited to, starch, methylcellulose, agar, bentonite, xanthan gum, and the like. For example, tablets are prepared by making a powder mixture, granulating or slugging, adding a lubricant and a disintegrant, and compressing into tablets. The powdered mixture is prepared by mixing the appropriately comminuted compound with a diluent or base as described above, optionally with a binder (for example carboxymethylcellulose, alginates, gelatin or polyvinylpyrrolidone), a dissolution inhibitor (for example paraffin), an absorption accelerator (quaternary salt) and/or an absorbent (for example bentonite, kaolin or dicalcium phosphate). The powdered mixture may be granulated by wetting with a binder such as syrup, starch slurry, acacia slurry (acadia mucilage) or a solution of cellulosic or polymeric material and pressure sieving. An alternative to granulation is to pass the powder mixture through a tablet press, with the result that poorly formed agglomerates are broken up into granules. The granules may be lubricated by the addition of stearic acid, a stearate salt, talc or mineral oil to prevent sticking to the dies of the tablet press. The lubricated mixture is then compressed into tablets. The compounds of the present disclosure may also be combined with a free-flowing inert carrier and compressed into tablets without going through a granulation or pre-compression step. Transparent or opaque protective coating materials may be provided which consist of a shellac coating, a sugar coating or a coating of a polymeric material and a waxy polishing coating (wax). Dyes may be added to these coatings to distinguish different unit doses.

Oral liquid preparations such as solutions, syrups and elixirs can be prepared in dosage unit form so that a given quantity contains a predetermined amount of the compound. Syrups can be prepared by dissolving the compound in a suitably flavored aqueous solution, while elixirs can be prepared through the use of non-toxic vehicles. Solubilizing agents and emulsifiers (e.g., ethoxylated isostearyl alcohols and polyoxyethylene sorbitol ethers), preservatives, flavoring additives (e.g., peppermint oil or natural sweeteners or saccharin or other artificial sweeteners), and the like may also be added.

Dosage unit formulations for oral administration may be microencapsulated, if appropriate. The formulations may also be formulated for extended or sustained release, for example by coating or embedding in a particulate material such as a polymer, wax or the like.

The compounds of the invention, particularly the compounds of formula (I) and pharmaceutically acceptable salts thereof, may also be administered in liposomal delivery systems, such as small unilamellar liposomes, large unilamellar liposomes, and multilamellar liposomes. Liposomes can be composed of a variety of phospholipids (e.g., cholesterol, octadecylamine, or phosphatidylcholine).

The compounds of the invention, especially the compounds of formula (I) and pharmaceutically acceptable salts thereof, may also be delivered by using the monoclonal antibody as a separate carrier to which the compound molecule is coupled. The compounds may also be conjugated to soluble polymers as targetable drug carriers. Such polymers may include polyvinylpyrrolidone, pyran copolymer, polyhydroxypropylmethacrylamide phenol, polyhydroxyethylaspartamide phenol, or polyethyleneoxide polylysine substituted with palmitoyl residues. In addition, the compounds may be coupled to a class of biodegradable polymers for achieving controlled release of a drug, such as polylactic acid, poly-caprolactone, polyhydroxybutyric acid, polyorthoesters, polyacetals, polydihydropyrans, polycyanoacrylates, and crosslinked or amphipathic block copolymers of hydrogels.

Pharmaceutical formulations adapted for transdermal administration may be presented as discrete patches (patches) to remain in intimate contact with the epidermis of the recipient for an extended period of time. For example, the active ingredient may be delivered by iontophoretic patches, as generally described in Pharmaceutical Research 1986,3(6), 318.

Pharmaceutical preparations suitable for topical administration may be formulated as ointments, creams, suspensions, lotions, powders, solutions, pastes, gels, sprays, aerosols, oils or transdermal patches.

Pharmaceutical formulations adapted for rectal administration may be presented as suppositories or as enemas.

Pharmaceutical formulations suitable for nasal administration, wherein the carrier is a solid, include coarse powders having a particle size in the range of, for example, 20 to 500 microns, which are administered by nasal inhalation, i.e. by rapid inhalation through the nasal passage from a coarse powder container adjacent the nose. Suitable formulations in which the carrier is a liquid, suitable for administration as a nasal spray or nasal drops, include aqueous or oily solutions of the active ingredient.

Pharmaceutical formulations suitable for administration by inhalation include finely divided particulate powders (dust) or mists (mist), which may be prepared in different types of metered dose compressed aerosols, nebulised inhalers, insufflators or other devices adapted to deliver aerosol sprays.

Pharmaceutical formulations adapted for vaginal administration may be presented as pessaries, tampons, creams, gels, pastes, foams or spray formulations.

Pharmaceutical formulations suitable for parenteral administration include aqueous and non-aqueous sterile injection solutions, which may contain antioxidants, buffers, bacteriostats and solutes that render the formulation isotonic with the blood of the recipient, and aqueous and non-aqueous sterile suspensions, which may include suspending agents and thickening agents. The formulations may be presented in unit-dose or multi-dose containers, for example sealed amkside and vials, and may be stored in a freeze-dried (lyophilized) condition requiring only the addition of the sterile liquid carrier, for example water for injections, immediately prior to use. The injection solution and suspension can be prepared into sterile powder for injection, granule and tablet.

It will be appreciated that in addition to the ingredients particularly mentioned above, the formulations may include other ingredients conventional in the art having regard to the type of formulation in question, for example, such formulations which are suitable for oral administration may include flavouring agents.

Use of the Compounds and pharmaceutical compositions of the invention

Pharmaceutical compositions of the invention may be characterized as comprising a compound of formula (I), a compound of the invention as set forth, or a compound of examples 1-2, and a pharmaceutically acceptable carrier, adjuvant, or vehicle. The compound in the composition can effectively inhibit the capacity of influenza virus, and is suitable for preventing and treating the influenza virus.

A method of treatment comprising administering a compound or pharmaceutical composition of the invention further comprising administering to a patient an additional anti-influenza drug, whereby the compound of the invention can be administered in combination therapy with the additional anti-influenza drug, wherein the anti-influenza drug is peramivir, zanamivir, oseltamivir, nannimivir, faviravir, amantadine, rimbidol, ribavirin, stafurin, Ingavirin (Ingavirin), GR-217029, or a combination thereof.

And a method of treatment comprising administration of a compound or pharmaceutical composition of the invention, further comprising administration of an additional anti-influenza agent, wherein the additional anti-influenza agent may be administered in combination with the compound or pharmaceutical composition of the invention as a single dosage form, or as separate compounds or pharmaceutical compositions as part of a multiple dosage form. Other anti-influenza agents may be administered simultaneously or non-simultaneously with the compounds of the invention. In the latter case, administration may be carried out by, for example, shifting between 6 hours, 12 hours, 1 day, 2 days, 3 days, 1 week, 2 weeks, 3 weeks, 1 month, or 2 months.

An "effective amount" or "effective dose" of a compound or pharmaceutically acceptable composition of the invention refers to an amount effective to treat or reduce the severity of one or more of the conditions mentioned herein. The compounds and compositions according to the methods of the present invention can be administered in any amount and by any route effective to treat or reduce the severity of the disease. The exact amount necessary will vary depending on the patient, depending on the race, age, general condition of the patient, severity of infection, particular factors, mode of administration, and the like. The compound or composition may be administered in combination with one or more other therapeutic agents, as discussed herein.

General Synthesis of the Compounds

In general, the compounds of the present invention may be prepared by the methods described herein, wherein the substituents are as defined in formula (I), unless otherwise indicated. The following reaction schemes and examples serve to further illustrate the context of the invention.

Those skilled in the art will recognize that: the chemical reactions described herein may be used to suitably prepare a number of other compounds of the invention, and other methods for preparing the compounds of the invention are considered to be within the scope of the invention. For example, the synthesis of those non-exemplified compounds according to the present invention can be successfully accomplished by those skilled in the art by modification, such as appropriate protection of interfering groups, by the use of other known reagents in addition to those described herein, or by some routine modification of reaction conditions. In addition, the reactions disclosed herein or known reaction conditions are also recognized as being applicable to the preparation of other compounds of the present invention.

The examples described below, unless otherwise indicated, are all temperatures set forth in degrees Celsius. Reagents were purchased from commercial suppliers such as Lingkai medicine, Aldrich Chemical Company, Inc., Arco Chemical Company and Alfa Chemical Company, and were used without further purification unless otherwise indicated. General reagents were purchased from Shantou Wen Long chemical reagent factory, Guangdong Guanghua chemical reagent factory, Guangzhou chemical reagent factory, Tianjin HaoLiyu Chemicals Co., Ltd, Qingdao Tenglong chemical reagent Co., Ltd, and Qingdao Kaseiki chemical plant.

The anhydrous tetrahydrofuran is obtained by refluxing and drying the metallic sodium. The anhydrous dichloromethane and chloroform are obtained by calcium hydride reflux drying. Ethyl acetate, N, N-dimethylacetamide and petroleum ether were used dried over anhydrous sodium sulfate in advance.

The following reactions are generally carried out under positive pressure of nitrogen or argon or by sleeving a dry tube over an anhydrous solvent (unless otherwise indicated), the reaction vial being stoppered with a suitable rubber stopper and the substrate being injected by syringe. The glassware was dried.

The column chromatography is performed using a silica gel column. Silica gel (300 and 400 meshes) was purchased from Qingdao oceanic chemical plants. Nuclear magnetic resonance spectroscopy with CDC1₃Or DMSO-d₆As solvent (reported in ppm) TMS (0ppm) or chloroform (7.25ppm) was used as reference standard. When multiple peaks occur, the following abbreviations will be used: s (singleton), d (doublet), t (triplet ), m (multiplet, multiplet), br (broad ), dd (doublet of doublets, quartet), dt (doublet of triplets). Coupling constants are expressed in hertz (Hz).

Low resolution Mass Spectral (MS) data were measured by an Agilent 6320 series LC-MS spectrometer equipped with a G1312A binary pump and a G1316A TCC (column temperature maintained at 30 ℃), a G1329A autosampler and a G1315B DAD detector were applied for analysis, and an ESI source was applied to the LC-MS spectrometer.

Low resolution Mass Spectral (MS) data were determined by Agilent 6120 series LC-MS spectrometer equipped with a G1311A quaternary pump and a G1316A TCC (column temperature maintained at 30 ℃), a G1329A autosampler and a G1315D DAD detector were used for analysis, and an ESI source was used for the LC-MS spectrometer.

Both spectrometers were equipped with an Agilent Zorbax SB-C18 column, 2.1X 30mm, 5 μm. The injection volume is determined by the sample concentration; the flow rate is 0.6 mL/min; peaks of HPLC were recorded by UV-Vis wavelength at 210nm and 254 nm. The mobile phases were 0.1% formic acid in acetonitrile (phase a) and 0.1% formic acid in ultrapure water (phase B). Gradient elution conditions are shown in table 1:

TABLE 1

Time (min)	A(CH₃CN，0.1％HCOOH)	B(H₂O，0.1％HCOOH)
			0-3	5-100	95-0
3-6	100	0
			6-6.1	100-5	0-95
6.1-8	5	95

Compound purification was assessed by Agilent 1100 series High Performance Liquid Chromatography (HPLC) with UV detection at 210nm and 254nm, a Zorbax SB-C18 column, 2.1X 30mm, 4 μm, 10 min, flow rate 0.6mL/min, 5-95% (0.1% formic acid in acetonitrile) in (0.1% formic acid in water), the column temperature was maintained at 40 ℃.

The following acronyms are used throughout the invention:

volume ratio of V/V, V/V

ul microliter

mol/L, M mol/L

mol mole of

mmol millimole

mL of

PE Petroleum ether (60-90 deg.C)

EA, EtOAc ethyl acetate

DIPEA N, N-diisopropylethylamine

TLC thin layer chromatography

The following synthetic schemes describe the steps for preparing the compounds disclosed herein.

Synthesis scheme I

The compounds (I) can be prepared by the synthesis scheme (I), wherein R¹And X has the meaning of the invention. The compound (1) and the compound (2) are subjected to one-step nucleophilic reaction under the action of alkali such as triethylamine, potassium carbonate and the like to obtain a target compound (3), and the compound (3) is subjected to reaction under the action of alkaline conditions such as potassium carbonate to obtain a target compound 4.

The compounds, pharmaceutical compositions and uses thereof provided by the present invention are further illustrated below in connection with the examples.

Examples

Example 1: 3- ((1, 3-dihydroxypropan-2-yl) amino) -6-fluoropyrazine-2-carboxamide

Step 1: synthesis of 6-bromo-3-hydroxypyrazine-2-carboxamide

3-hydroxypiperazine-2-carboxamide (5g,35.97mmol,1eq.) and tetrabutylammonium bromide (19g,39.57mmol,1.1eq.) were dissolved in N, N-dimethylformamide (50mL), followed by the addition of 2, 6-lutidine (4.2mL,35.97mmol,1 eq.). The mixture was stirred at room temperature for 17 hours and the reaction was monitored by TLC until complete. After completion of the reaction, a 10% aqueous solution (100mL) of sodium chloride was added to the reaction system to precipitate a solid. The solid was collected and added to a mixed solution of 30mL of water and 30mL of ethyl acetate, stirred for 10 minutes, and the organic phase was separated. The organic phase was washed with saturated brine (20mL × 2), dried over anhydrous sodium sulfate, and concentrated under reduced pressure to give crude residue, which was then purified by silica gel column chromatography (eluent: PE/EA (V/V) ═ 5/1-2/1) to give 4g of compound as a white solid in 51% yield.

MS-ESI:(ESI,pos.ion)m/z:219.1[M+1]⁺。

Step 2: synthesis of 6-bromo-3-chloropyrazine-2-carbonitrile

6-bromo-3-hydroxypyrazine-2-carboxamide (3.57g,16.38mmol,1eq.) was dissolved in chlorobenzene (70mL), and phosphorus oxychloride (5.3mL,57.33mmol,3.5eq.) and N, N-diisopropylethylamine (11.4mL,65.52mmol,4eq.) were added at 0 ℃. The mixture was heated to 100 ℃ and stirred for 17 hours, and the progress of the reaction was observed by TLC. The reaction mixture was concentrated under reduced pressure to give a crude product, which was purified by silica gel column chromatography (eluent: PE/EA (V/V) ═ 15/1-10/1) to give 2.2g of a compound as a white solid in 62% yield.

And step 3: synthesis of 3, 6-difluoropyrazine-2-carbonitrile

Potassium fluoride (5.7g,98.44mmol,3.7eq.) and tetrabutylammonium bromide (1.72g,5.32mmol,0.2eq.) were added to 10mL of anhydrous dimethyl sulfoxide, and the mixture was heated to 100 ℃ for 1 hour. The temperature was reduced to 70 ℃ and 20mL of an anhydrous toluene solution of 6-bromo-3-chloropyrazine-2-carbonitrile (5.8g,26.6mmol,1eq.) was added, and the mixture was reacted at this temperature for 3 hours. After TLC monitoring of the reaction, 10mL of water was added and the organic phase was separated. The organic phase is washed with 20mL of saturated brine, then hydrochloric acid is added to adjust the pH to about 1.6, the organic phase is successively washed with 20mL of saturated sodium chloride solution, dried over anhydrous sodium sulfate and concentrated under reduced pressure to give the crude product. The crude product was further purified by silica gel column chromatography (eluent: PE/EA: 30/1) to give 1.85g of a white solid product in 49% yield.

¹H NMR(400MHz,CDCl₃):8.34-8.31(d,1H)。

And 4, step 4: synthesis of 3- ((1, 3-dihydroxypropan-2-yl) amino) -6-fluoropyrazine-2-carbonitrile

3, 6-Difluoropyrazine-2-carbonitrile (200mg,1.42mmol), 2-aminopropan-1, 2-diol (142mg,1.56mmol) and triethylamine (0.43mL,3.12mmol) were added to 30mL dichloromethane, the mixture was stirred at room temperature for 2 hours, and the reaction was monitored by TLC until the reaction was complete. 20mL of water was added thereto, and the organic phase was washed with 20mL of saturated brine, dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: PE/EA: 2/1) to give 55mg of the objective compound as a white solid in a yield of 19%.

MS-ESI:(ESI,pos.ion)m/z:213.1[M+1]⁺。

And 5: synthesis of 3- ((1, 3-dihydroxypropan-2-yl) amino) -6-fluoropyrazine-2-carboxamide

Potassium carbonate (66mg,0.48mmol) was dissolved in water (0.66mL), the solution was added to a solution of 3- ((1, 3-dihydroxypropan-2-yl) amino) -6-fluoropyrazine-2-carbonitrile (55mg,0.24mmol) in dimethylsulfoxide (4mL) at 10 ℃, and then the reaction solution was stirred at room temperature for 30 minutes. A30% hydrogen peroxide solution (0.1mL,1.2mmol) was added to the reaction system, and the reaction was continued at room temperature for 2 hours. After the completion of the reaction was monitored by TLC, 20mL each of ethyl acetate and water was added, the mixture was separated, and the organic phase was washed with saturated brine (15 mL. times.2), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was subjected to silica gel column chromatography (eluent: PE/EA: 4/1) to give the objective compound (8.5 mg) as a white solid in a yield of 14%.

MS-ESI:(ESI,pos.ion)m/z:231.2[M+1]⁺；

¹H NMR(400MHz,DMSO):8.75(d,1H),8.33(d,1H),8.00(s,1H),7.68(s,1H),4.79(t,1H),4.03(dd,2H),3.53(m,4H)。

Example 2: 6-fluoro-3- ((3-hydroxypropyl) amino) pyrazine-2-carboxamide

Step 1: synthesis of 6-fluoro-3- ((3-hydroxypropyl) amino) pyrazine-2-carbonitrile

3, 6-Difluoropyrazine-2-carbonitrile (100mg,0.70mmol), 3-aminopropan-1-ol (58mg,0.78mmol) and triethylamine (0.21mL,1.1mmol) were placed in 50mL dichloromethane, the mixture was stirred at room temperature for about 2 hours, and after completion of the TLC monitoring reaction, dichloromethane was removed by concentration under reduced pressure. The residue was purified by silica gel column chromatography (eluent: PE/EA: 2/1) to give 83mg of the objective compound as a white solid in a yield of 56%.

MS-ESI:(ESI,pos.ion)m/z:197.1[M+1]⁺。

Step 2: synthesis of 6-fluoro-3- ((3-hydroxypropyl) amino) pyrazine-2-carboxamide

6-fluoro-3- ((3-hydroxypropyl) amino) pyrazine-2-carbonitrile (77mg,0.39mmol) was dissolved in dimethyl sulfoxide (4mL), and an aqueous solution (1mL) of potassium carbonate (107mg,0.78mmol) was added to the solution at 10 ℃ and the mixture was allowed to warm to room temperature for 30 minutes. Then 30% aqueous hydrogen peroxide (221mg,1.95mmol) was added and the mixture was stirred at room temperature for an additional 2 hours. After the completion of the reaction was monitored by TLC, 20mL each of ethyl acetate and water was added and the mixture was separated. The organic phase was washed with saturated brine (15mL × 2), dried over anhydrous sodium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent PE: EA ═ 2:1) to give the target compound 42mg as a white solid in a yield of 50%.

MS-ESI:(ESI,pos.ion)m/z:215.2[M+1]⁺；

¹H NMR(400MHz,CDCl₃):8.54(s,1H),8.10(dd,1H),7.38(s,1H),5.60(s,1H),3.61-3.67(m,4H),2.33-2.35(d,2H),1.80-1.86(m,2H)。

Determination of anti-influenza Virus Activity

96-well plate CPE assay procedure:

spreading in 96-well plate, inoculating 5000 MDCK cells in each well, 37 deg.C, 5% CO₂And culturing overnight.

Compounds were diluted to appropriate concentrations with DMSO and serum-free medium to a final DMSO concentration of 1%.

The frozen influenza virus H1N1(A/weiss/43) was diluted with medium at-80 ℃.

50ul of diluted compound and 50ul of diluted virus fluid (final MOI 0.01) were added per well.

The 96-well plate was placed at 37 ℃ in 5% CO₂And culturing for 3 days.

20ul of MTT was added to each well and incubated at 37 ℃ for 4 hours.

The amount of formazan reduced by live cells from MTT was measured and based thereon the percentage of influenza virus-mediated inhibition of CPE by the test compound was calculated.

96-well plate cytotoxicity assay procedure:

50ul of diluted compound and 50ul of culture medium were added to each well.

The 96-well plate was placed at 37 ℃ in 5% CO₂And culturing for 3 days.

20ul of MTT was added to each well and the mixture was incubated at 37 ℃ for 4 hours.

The amount of formazan reduced by a living cell from MTT was measured, and the cytotoxicity of the test compound was calculated based on the amount.

And (3) data analysis:% inhibition ═ OD_T–OD_V)/(OD_C–OD_V)×100％

% cytotoxicity ═ OD_T/OD_C×100％

% activity ═ inhibition [% cytotoxicity [% ]

OD_T,OD_VAnd OD_CRespectively, the absorbance coefficient for the test compound, the virus infection control (no compound, + 1% DMSO),

and cell blank (no virus, no compound, + 1% DMSO)

OD value＝OD₅₇₀–OD₆₃₀(MTT)

Table 2: the partial compound of the invention has in vitro experiment activity value on influenza virus H1N1(A/weiss/43)

As can be seen from the above table, the compound of the present invention has significant anti-influenza virus activity.

It will be evident to those skilled in the art that the present disclosure is not limited to the foregoing illustrative embodiments, but may be embodied in other specific forms without departing from the essential characteristics thereof. The present embodiments are, therefore, to be considered in all respects as illustrative and not restrictive, reference being made to the appended claims, rather than to the foregoing embodiments, and all changes which come within the meaning and range of equivalency of the claims are therefore intended to be embraced therein.

In the description herein, references to the description of the term "one embodiment," "some embodiments," "an example," "a specific example" or "some examples" or the like are intended to mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the invention. In this specification, the schematic representations of the terms used above do not necessarily refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.

Although embodiments of the present invention have been shown and described above, it is understood that the above embodiments are exemplary and should not be construed as limiting the present invention, and that those skilled in the art can make changes, modifications, substitutions and alterations to the above embodiments without departing from the principle and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A compound which is a stereoisomer, a geometric isomer, a tautomer, a pharmaceutically acceptable salt of a structural formula shown in formula (I) or a structure shown in formula (I),

wherein,

x is halogen; and

R¹is C₁-C₆A hydroxyalkyl group.

2. The compound of claim 1, wherein,

x is F, Cl, Br or I; and

R¹is C₁-C₆A hydroxyalkyl group.

3. The compound of claim 1, wherein R¹Is 3-hydroxypropyl, 2-hydroxypropyl, 1-hydroxypropyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1, 3-dihydroxypropan-2-yl, hydroxybutyl, 2, 4-dihydroxybutyl, hydroxypentyl or hydroxyhexyl.

4. The compound of claim 1, which is a structure of formula (II) or a stereoisomer, geometric isomer, tautomer, pharmaceutically acceptable salt of a structure of formula (II),

wherein R is¹Is C₁-C₆A hydroxyalkyl group.

5. The compound of claim 4, wherein R¹Is 3-hydroxypropyl, 2-hydroxypropyl, 1-hydroxypropyl, hydroxymethyl, 1-hydroxyethyl, 2-hydroxyethyl, 1, 3-dihydroxypropan-2-yl, hydroxybutyl, 2, 4-dihydroxybutyl, hydroxypentyl or hydroxyhexyl.

6. The compound of claim 1, having one of the following structures,

or a stereoisomer, geometric isomer, tautomer, pharmaceutically acceptable salt of the structure shown.

7. A pharmaceutical composition comprising a compound of any one of claims 1-6, and a pharmaceutically acceptable carrier, excipient, diluent, or combination thereof.

8. The pharmaceutical composition of claim 7, further comprising an additional anti-influenza virus drug, wherein the anti-influenza virus drug is peramivir, zanamivir, oseltamivir, nannie nanowivir, favipiravir, amantadine, rimantadine, ribavirin, stafurin, Ingavirin (Ingavirin), or a combination thereof.

9. Use of a compound according to any one of claims 1 to 6 or a pharmaceutical composition according to any one of claims 7 to 8 in the manufacture of a medicament for the prevention, treatment or alleviation of a disease or a disorder associated with an influenza virus.