5-[is right-(2-pyridine sulfamic) benzene] and the Olsalazine purifying process
Technical field:
The present invention relates to the synthetic field of medicine, be specifically related to 5-[right-(2-pyridine sulfamic) benzene] purifying process of Olsalazine.
Background technology:
5-(right-(2-pyridine sulfamic) benzene) Olsalazine, general sulfasalazine by name (SASP) has following formula I structure
SASP is mainly used in the treatment nonspecific ulcerative colitis, and this product has special avidity to reticular tissue, and plays therapeutic action, the clinical rheumatic arthritis that also is used for the treatment of to discharge sulfapyridine and 5-aminosalicylic acid in the intestines wall.Although this product is an old product, the market requirement is still very big, and is especially more and more higher to its specification of quality.
The synthetic of SAPA normally is that starting raw material obtains intermediate SP (II) through amination and condensation with the pyridine, reaches and the Acidum Salicylicum coupling by diazotization then, obtains finished product SASP (I), and reaction formula is formula as follows:
Through above-mentioned reaction, the impurity that has in the finished product crude product is a lot, and the impurity of known structure has nine, comprising:
A, 4,4 '-[(4-hydroxyl-1,3-phenylene) two (diazenediyls)] two [N-(pyridine-2-yl) benzsulfamide.
B, 2-hydroxyl-3,5-two [2-(4-(pyridine-2-base sulfoamido) phenyl) diazenyl] phenylformic acid.
C, 2-hydroxyl-5-[2-[4-(2 aminopyridine-1 (2H)-yl) phenyl] diazenyl] phenylformic acid:
D, 4-[2-(2-hydroxy phenyl) diazenyl]-N-(pyridine-2 base) benzsulfamide:
E, 2-hydroxyl-4 '-(pyridine-2-base sulfoamido)-5-[2-[4-(pyridine-2-base sulfoamido) phenyl] diazenyl] phenylbenzene-3-carboxylic acid:
F, 2-hydroxyl-3-[2-[4-(pyridine-2-base sulfoamido) phenyl] diazenyl] phenylformic acid
G, 5-[2-[4 ', 5 two (pyridine-2-base sulfoamido) phenylbenzene-2-yl] diazenyl]-2 hydroxybenzoic acid:
H, Whitfield's ointment
I, 2-hydroxyl-5-[2-(4-benzenesulfonyl) diazenyl] phenylformic acid:
Be B, E, F wherein, in treating process, be difficult to remove to the most similar impurity of finished product character.
Reaching conventional process for purification according to the literature is the SASP crude product to be refluxed with Glacial acetic acid remove alkaline impurities, after the centrifugation, is dissolved in alkaline solution again, the acquisition finished product of saltouing after the decolouring.Used acid, the alkali number of this method is big, and yield is low, and equipment corrosion is serious, and the three wastes are difficult to handle, and final product quality is difficult to reach the regulation of European Pharmacopoeia.
Summary of the invention:
Technical problem to be solved by this invention is to improve existing SASP process for purification, and a kind of economy, easy is provided, and removes the more effective significant method of impurity.
SASP purification process disclosed by the invention comprises the following steps:
(1) in the SASP crude product, add 2~6 times 15~70% the DMF aqueous solution, heated and stirred slowly adds alkali, to all dissolvings;
(2) drip acid in above-mentioned solution, maintenance pH is 1-3,60~95 ℃ of temperature, and fully centrifuging promptly gets half highly finished product behind the acid out;
(3) above-mentioned half highly finished product are added alkali dissolution in the aqueous solution, add heat decoloring, filter, filtrate is adjusted to pH1-3 with acid, filters, and is drying to obtain;
(4) the DMF solution behind step (2) the separation finished product is applied mechanically after underpressure distillation is handled.
Alkali of the present invention and acid are acid or alkali such as industrial nitric acid, hydrochloric acid and industrial solid sodium hydroxide or liquid sodium hydroxide commonly used.
The present invention has carried out a series of groping to SASP crude product refining method:
(1) the nitration mixture pickling refluxes and carries highly acid pH value, can play certain effect to removing impurity, but undesirable, can't reach the specification of quality of EP4 version.
(2) add elutriation with the neat solvent dissolving and go out, cold filtration is refining, and the result separates out impurity simultaneously, and it is not obvious to remove impurity; If the filtered while hot yield is low, it is big to reclaim quantity of solvent simultaneously, and neat solvent must be gone up column distillation, and energy consumption is big, and production schedule is slow, and yield is on the low side.
(3) mixed solvent refluxes to wash and can only remove less impurity, mainly is the complete molten process of none, and this method is also inadvisable.
Adopt the thin plate layer analysis method to detect, the impurity spot of SASP mainly is that two significantly big impurity spots are being arranged on the point of sample and under the principal spot, with the Glacial acetic acid reflow method mainly is the impurity spot of removing on the point of sample, i.e. diamino-pyridine impurity (impurity numbering C).With becoming the sodium salt method mainly to remove impurity spot principal spot under, i.e. Whitfield's ointment impurity, effect is relatively good, and the impurity spot effect that Glacial acetic acid is washed is not remarkable.
With the method for DMF mixed solvent of the present invention, can remove above-mentioned two major impurities simultaneously, and can remove other impurity in a small amount.Its major cause is at first crude product to be dissolved fully, according to the character of product, the product acid out is come out again, and the impurity that is wrapped in the crude product solid is fully separated.To compare effect obvious with methods such as former pickling.
Adopt process for purification of the present invention, have following distinguishing feature:
1, it is obvious to remove impurity, and final product quality meets the requirement of Chinese Pharmacopoeia 2000 editions, BP2000 version, Ph.Eur.4 version fully, and the T degree requires can satisfy various requirement simultaneously, accomplishes fluently solid foundation for pharmacopeia from now on rises version.Just contrasting as can be seen from the stratographic analysis figure (Fig. 1) that improves the back finished product stratographic analysis figure (Fig. 2) that produces and original finished product, 9 impurity obviously reduce.
2, improve 15% by the refining yield of process modification.
3, easy and simple to handle, easy to control with novel process, low to equipment corrosion, shorten the production cycle and reduced labour intensity, the labour protection aspect is had more reasonableness.
4, the solvent employing is applied mechanically in the improvement technology, deals impurity simultaneously and also can focus on solid form, and the three wastes obviously reduce.
Description of drawings:
The former explained hereafter of Fig. 1 obtains the HPLC collection of illustrative plates of SASP
Fig. 2 obtains the HPLC collection of illustrative plates of SASP with explained hereafter of the present invention
Wherein I, C, G, B, A are impurity peaks.
Embodiment:
Embodiment 1
SASP crude product 30g and 60g70%DMF solution are dropped in the 250ml reaction flask, open and stir, heating, add solid NaOH, regulate pH to 7.5~8.5 in 60 ℃, complete molten after, insulation, drip HCL to pH2.0~2.5, filter, the filter cake hot wash is drained, get SASP-I, mother liquor DMF recovery set after underpressure distillation is handled is used.SASP-I is dropped in the deionized water of 20 times of amounts, add NaOH, heating for dissolving is regulated pH to 7.5~8.5, add proper amount of active carbon after molten entirely in 70 ± 2 ℃ of insulation decolourings, filter, filtrate is adjusted to pH2.0~2.5 with hydrochloric acid, filters, the filter cake hot wash, dry the SASP finished product, refining yield 80.33%, the gained final product quality meets EP4.(seeing collection of illustrative plates 2)
Embodiment 2
SASP crude product 30g and 120g15%DMF solution are dropped in the 250ml reaction flask, open and stir, heating, add solid NaOH, with 80 ℃ regulate pH to 7.5~8.5, complete molten after, insulation, drip HCL to pH2.0~2.5, filter, the filter cake hot wash is drained, get SASP-I, mother liquor DMF recovery set after underpressure distillation is handled is used.SASP-I is dropped in the deionized water of 20 times of amounts, add NaOH, heating for dissolving is regulated pH to 7.5~8.5, add proper amount of active carbon after molten entirely in 70 ± 2 ℃ of insulation decolourings, filter, filtrate is adjusted to pH2.0~2.5 with hydrochloric acid, filters, the filter cake hot wash, dry the SASP finished product, refining yield 81.66%, the gained final product quality meets EP4.
Embodiment 3
SASP crude product 30g and 150G45%DMF solution are dropped in the 250ml reaction flask, open and stir, heating, add solid NaOH, with 60 ℃ regulate pH to 7.5~8.5, complete molten after, insulation, drip HCL to pH2.0~2.5, filter, the filter cake hot wash is drained, get SASP-I, mother liquor DMF recovery set after underpressure distillation is handled is used.SASP-I is dropped in the deionized water of 20 times of amounts, add NaOH, heating for dissolving is regulated pH to 7.5~8.5, add proper amount of active carbon after molten entirely in 70 ± 2 ℃ of insulation decolourings, filter, filtrate is adjusted to pH2.0~2.5 with hydrochloric acid, filters, the filter cake hot wash, dry the SASP finished product, refining yield 79.33%, the gained final product quality meets EP4.
Embodiment 4
SASP crude product 30g and 180g30%DMF solution are dropped in the 250ml reaction flask, open and stir, heating, add solid NaOH, with 65 ℃ regulate pH to 7.5~8.5, complete molten after, insulation, drip HCL to pH2.0~2.5, filter, the filter cake hot wash is drained, get SASP-I, mother liquor DMF recovery set after underpressure distillation is handled is used.SASP-I is dropped in the deionized water of 20 times of amounts, add NaOH, heating for dissolving is regulated pH to 7.5~8.5, add proper amount of active carbon after molten entirely in 70 ± 2 ℃ of insulation decolourings, filter, filtrate is adjusted to pH2.0~2.5 with hydrochloric acid, filters, the filter cake hot wash, dry the SASP finished product, refining yield 80.33%, the gained final product quality meets EP4.