KR900003501B1 - Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives - Google Patents
Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives Download PDFInfo
- Publication number
- KR900003501B1 KR900003501B1 KR1019870005549A KR870005549A KR900003501B1 KR 900003501 B1 KR900003501 B1 KR 900003501B1 KR 1019870005549 A KR1019870005549 A KR 1019870005549A KR 870005549 A KR870005549 A KR 870005549A KR 900003501 B1 KR900003501 B1 KR 900003501B1
- Authority
- KR
- South Korea
- Prior art keywords
- general formula
- methyl
- group
- dioxide
- benzothiazine
- Prior art date
Links
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07D—HETEROCYCLIC COMPOUNDS
- C07D513/00—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for in groups C07D463/00, C07D477/00 or C07D499/00 - C07D507/00
- C07D513/02—Heterocyclic compounds containing in the condensed system at least one hetero ring having nitrogen and sulfur atoms as the only ring hetero atoms, not provided for in groups C07D463/00, C07D477/00 or C07D499/00 - C07D507/00 in which the condensed system contains two hetero rings
- C07D513/04—Ortho-condensed systems
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Pharmaceuticals Containing Other Organic And Inorganic Compounds (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
Description
본 발명은 옥사지노벤조티아진 6,6-디옥사이드 유도체의 제조방법에 관한 것으로서, 특히 5-메틸-3-헤테로아릴-2H,5H-1,3-옥사지노[5,6-c][1, 2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드 유도체의 제조방법에 관한 것이다.The present invention relates to a method for preparing an oxazinobenzothiazine 6,6-dioxide derivative, in particular 5-methyl-3-heteroaryl-2H, 5H-1,3-oxazino [5,6-c] [1 , 2] benzothiazine-2,4- (3H) -dione 6,6-dioxide derivative.
본 발명에 따른 다음의 일반식(I )로 표시되는 5-메틸-3-헤테로아릴-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드 유도체는 수득물이 높고 매우 순수한 형태로 얻어지게 되는바,5-Methyl-3-heteroaryl-2H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine-2 represented by the following general formula (I) according to the present invention , 4- (3H) -dione 6,6-dioxide derivative is obtained in a high purity and very pure form,
상기 R이 헤테로아릴기, 그중에서도 바람직하게로는 치환 혹은 비치환 피리미디닐이나 피리딜기인 경우에 해당 되는 상기 일반식(I)로 표시되는 옥사지노벤조티아진 6,6-디옥사이드는 소염제와 진통제, 특히 드록시캄(droxicam)으로 널리 알려져 있고 Chem. Abst.(1984, 100, 191893j)에 기재되어있다.The oxazinobenzothiazine 6,6-dioxide represented by the general formula (I) corresponding to the case where R is a heteroaryl group, preferably substituted or unsubstituted pyrimidinyl or pyridyl group, is an anti-inflammatory agent and an analgesic agent. , Especially droxicam, and Chem. Abst. (1984, 100, 191893j).
종래의 기술에서는 옥사지노벤조티아진 6,6-디옥사이드를 다음 일반식(II)로 표시되는 에스테르로부터 제조하였는데,In the prior art, oxazinobenzothiazine 6,6-dioxide was prepared from an ester represented by the following general formula (II),
이때 R1은 메톡시나 에톡시기와 같은 알콕시기를 나타낸다.R 1 represents an alkoxy group such as methoxy or ethoxy group.
또한, 프랑스 특허 A-2 566 408호에는 상기 R1이 피리딘-2-일아미노기를 나타내는 상기 일반식(II)로 표시되는 화합물을 그 반응조건하에서 불활성인 유기용매 존재하에서 그리고 산수용체의 존재하에서 포스겐과 반응시켜서 5-메틸-3-(피리딘-2-일)-2H,5H-1,3옥사지노[5,6-c]-1,2-벤조티아진-2,4-(3H)-디온 6,6-디옥사이드를 제조하는 방법이 기재되어 있으며, 여기서는 상기 공정의 경제성과 수득를이 가장 좋게 되도록 하기 위하여 메틸렌 클로라이드를 유기용매로서 사용하고 산수용체로는 트리에틸아민을 사용하는 것이 바람직하다고 설명되어 있으나, 이러한 유형의 방법은 특히 공업적인 규모로 실행될 때 우선 상당히 유독한 제제인 포스겐을 사용한다는 점과 그 수득률이 56% 정도로 매우 낮다는 점과 같은 단점이 있는 등 심각한 문제짐이 있었다.Further, French Patent A-2 566 408 discloses a compound represented by the above general formula (II) wherein R 1 represents a pyridin-2-ylamino group in the presence of an organic solvent which is inert under the reaction conditions and in the presence of an acid acceptor. Reacted with phosgene to react with 5-methyl-3- (pyridin-2-yl) -2H, 5H-1,3oxazino [5,6-c] -1,2-benzothiazine-2,4- (3H) A method for producing di-ion 6,6-dioxide is described, where methylene chloride is used as the organic solvent and triethylamine is preferred as the acid acceptor in order to obtain the best economics and yield of the process. Although described, this type of method has serious problems, including the disadvantages of using phosgene, which is a fairly toxic agent, especially when carried out on an industrial scale, and its yield is very low, such as 56%.
따라서, 본 발명은 상기와 같은 종래기술의 문제점을 해결하기 위해 간단한 공정을 거쳐서 순수한 형태이면서 수득률도 높게 되도록 하는 상기 일반식(I)로 표시되는 옥사지노벤조티아진 6,6-디옥사이드 유도체의 신규한 제조방법을 제공하는데 그 목적이 있다.Therefore, the present invention is a novel form of the oxazinobenzothiazine 6,6-dioxide derivative represented by the above general formula (I) to be a pure form and high yield through a simple process to solve the problems of the prior art as described above. It is an object to provide a manufacturing method.
이하 본 발명을 상세히 설명하면 다음과 같다.Hereinafter, the present invention will be described in detail.
본 발명은 상기 일반식(II)로 표시되는 아미드를 다음 일반식(III)로 표시되는 화합물과 반응시켜 상기 일반식(I)로 표시되는 옥사지노벤조티아진 6,6-디옥사이드 유도체를 제조하는 방법인 것이다.The present invention reacts the amide represented by the general formula (II) with the compound represented by the following general formula (III) to prepare an oxazinobenzothiazine 6,6-dioxide derivative represented by the general formula (I). It is a way.
이때 상기 일반식(II)에서 R1은 헤테로아릴 아미노기를 나타내고, 치환 혹은 비치환 피리미디닐 아미노기 또는 피리딜 아미노기가 바람직하며, 상기 일반식(Ⅲ)에서 R2는 메틸이나 에틸기 같은 C1-C4저급 알킬기이거나 페닐기 같은 아릴기, 또는 벤질기와 같은 알킬아릴기를 나타낸다.In this formula (II), R 1 represents a heteroaryl amino group, a substituted or unsubstituted pyrimidinyl amino group or a pyridyl amino group is preferable, in the general formula (III) R 2 is a C 1 -such as methyl or ethyl group Or a C 4 lower alkyl group or an aryl group such as a phenyl group, or an alkylaryl group such as a benzyl group.
본 발명에 있어서, 상기 일반식(II)와 (Ⅲ)의 화합물물은 약-5℃ 내지 50℃ 사이의 온도에서 약 3 내지48시간 동안 반응시키게 된다.In the present invention, the compounds of the general formula (II) and (III) is allowed to react for about 3 to 48 hours at a temperature between about -5 ℃ to 50 ℃.
또한, 본 발명에서 중요한 것 중 하나는 상기 두가지 화합물을 4-디메틸아미노피리딘과 4-(피로리딘-1-일)피리딘 및 2,6-디터셔리-부틸-4-메틸피리딘 등의 치환피러딘과 피리딘 및 이들의 혼합물 중에서 선택되어진 유기용매 중예서 반응시킨다는 것인테, 이때 사용되는 용매가 피리딘과 치환 피리딘의 혼합물일 때,치환 피리딘은 1 내지 10% 정도의 중량비로 소량 사용하게 된다.In addition, one important thing in the present invention is substituted pyridines such as 4-dimethylaminopyridine, 4- (pyrrolidin-1-yl) pyridine and 2,6-di-butyl-4-methylpyridine. And pyridine and an organic solvent selected from a mixture thereof. When the solvent used is a mixture of pyridine and substituted pyridine, substituted pyridine is used in a small amount in a weight ratio of about 1 to 10%.
상기와 같은 본 발명에 따르면, 상당히 고순도의 상기 일반식(I )로 표시되는 화합물의 유도체를 얻게 된뿐만 아니라 공업적 규모로 실시할 수 있을 정도로 매우 공정이 간단하면서도 90% 이상의 수득률을 낼 수 있는 공정에 의해서 이러한 유도체를 얻게 된다.According to the present invention as described above, not only can be obtained a derivative of the compound represented by the general formula (I) of a very high purity, but also the process is very simple enough to be carried out on an industrial scale can yield 90% or more. The process yields these derivatives.
이하 본 발명에 따른 상기 일반식(I )로 표시되는 화합물의 몇가지 유도체를 제조하는 방법에 대해서 다음의 실시예 1 내지 4에서 상세히 설명하고 있으나 본 발명이 반드시 다음의 실시예에만 한정되는 것은 아니다.Hereinafter, a method of preparing some derivatives of the compound represented by Formula (I) according to the present invention will be described in detail in Examples 1 to 4 below, but the present invention is not necessarily limited to the following examples.
[실시예 1]Example 1
5-메틸-3-(피리딘-2-일)-2H,5H-1,3-옥사지노-[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드의 제조방법5-Methyl-3- (pyridin-2-yl) -2H, 5H-1,3-oxazino- [5,6-c] [1,2] benzothiazine-2,4- (3H) -dione Method for preparing 6,6-dioxide
301의 무수피리딘에 11.9kg(36몰)의 N-(피리딘-2-일)-4-하이드록시-2-메틸-2H-1,2-벤조티아진-3-카복사미드 1,1-디옥사이드를 용해시켜서 된 부분용액에 13.8ℓ(144몰)의 메틸 클로로포메이트를 교반시키면서 한방울씩 첨가시키되, 이때 온도를 계속 18℃ 이하로 유지시키면서 얼음조에서 냉각시킨다. 그 다음에 이 혼합물을 24시간 동안 상온에서 교반시키고 그 전량을 175ℓ의 물/얼음 혼합액에 붓는다. 이를 여과시킨 다음 그 잔류물을 다량의 증류수와 0.5N 염산 및 증류수로 차례로 세척시키며, 이때 얻어진 잔류물을 아세톤에 용해시켜서 융점 이 264-266℃ 인 5-메 틸-3-(피리딘-2-일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드 결정을 11.62kg(90.5%) 얻는다.11.9 kg (36 moles) of N- (pyridin-2-yl) -4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide 1,1- in 301 anhydrous pyridine 13.8 L (144 mol) of methyl chloroformate was added dropwise to the partial solution by dissolving the dioxide, while cooling in an ice bath while maintaining the temperature below 18 ° C. The mixture is then stirred for 24 hours at room temperature and the whole is poured into 175 L of water / ice mixture. After filtration, the residue was washed sequentially with a large amount of distilled water, 0.5N hydrochloric acid and distilled water, and the obtained residue was dissolved in acetone to give 5-methyl-3- (pyridine-2- having a melting point of 264-266 ° C. 11.62 kg (90.5%) of 2-H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine-2,4- (3H) -dione 6,6-dioxide crystals; )
분광데이타Spectral Data
IR(KBr) ; 1185 ; 1355 ; l410 ; 1640 ; 1710 ; 1790cm-1 IR (KBr); 1185; 1355; l410; 1640; 1710; 1790 cm -1
1H NMR, δ, [DMSO-d6] : 3.02(s,3H) ; 7.52(m,2H) ; 7.29(m,5H) ; 8.52(d, H) 1 H NMR, δ, [DMSO-d 6 ]: 3.02 (s, 3H); 7.52 (m, 2 H); 7.29 (m, 5 H); 8.52 (d, H)
[실시예 2]Example 2
5-메틸-3-(피리미딘-2-일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드의 제조5-methyl-3- (pyrimidin-2-yl) -2H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine-2,4- (3H) -dione Preparation of 6,6-Dioxide
25㎖의 무수피리딘에 3.32kg(0.01몰)의 N-(피리미딘-2-일)-4-하이드록시-2-메틸-2H-1,2-벤조티아진-3-카복사미드1,1-디옥사이드를용해시켜서 된 부분용액에다13.6g(0.04몰)의 벤질클로로포메이트를 톨루엔 내에 50% 용액으로 용해시켜서 된 용액을 교반시키면서 한방울씩 첨가시키되, 이때 온도를 계속10℃ 이하로 유지시키면서 얼음조에서 냉각시킨다. 이 혼합물을 30℃의 온도에서 8시간 동안 교반시킨 다음그 전량을 100㎖의 물/얼음 혼합액에 붓고 이를 여과시킨 다음 그 잔류물을 다량의 증류수로 세척시키고 나서 끓을 정도로 가열시킨 아세톤에서 즉시 교반시킨 후 그 혼합물을 여과시킨다.3.32 kg (0.01 mole) N- (pyrimidin-2-yl) -4-hydroxy-2-methyl-2H-1,2-benzothiazine-3-carboxamide 1 in 25 ml anhydrous pyridine, 13.6 g (0.04 mole) of benzylchloroformate was dissolved in toluene as a 50% solution in a partially dissolved solution of 1-dioxide, and the resulting solution was added dropwise while stirring while keeping the temperature below 10 ° C. Cool in an ice bath. The mixture was stirred for 8 hours at a temperature of 30 ° C. and then the whole amount was poured into 100 ml of water / ice mixture, filtered and the residue was washed with a large amount of distilled water and immediately stirred in acetone heated to boiling. The mixture is then filtered.
이와 같이 하면 융점이 282-284℃인 5-메틸-3-(피리미딘-2-일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드 화합물을 3.3g(92%)얻게 된다.This gives 5-methyl-3- (pyrimidin-2-yl) -2H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine with a melting point of 282-284 ° C. 3.3 g (92%) of -2,4- (3H) -dione 6,6-dioxide compound are obtained.
분광데이타Spectral Data
IR(KBr) ; 1180 ; 1355 ; 1400 ; 1632 ; 1710 ; 1787cm-1 IR (KBr); 1180; 1355; 1400; 1632; 1710; 1787 cm -1
1H NMR, δ, [DMSO-d6] : 3.05(s,3H) ; 7.93(m,5H) ; 8.95(d, H) 1 H NMR, δ, [DMSO-d 6 ]: 3.05 (s, 3H); 7.93 (m, 5 H); 8.95 (d, H)
[실시예 3]Example 3
5-메틸-3-(4-메틸피리딘-2-일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드의 제조5-methyl-3- (4-methylpyridin-2-yl) -2H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine-2,4- (3H) Preparation of -dione 6,6-dioxide
2g의 4-디메틸아미노피리딘과 25㎖의 무수피리딘 혼합물에 3.45g(0.01몰)의 N-(4-메틸피리딘-2-일)-4-하이드록시-2-메틸-2H-1,2-벤조티아진-3-카복사미드 1,1-디옥사이드를 용해시켜서 된 부분용액에다 5㎖(0.04몰)의 페닐클로로포메이트를 상온에서 교반시키면서 첨가시킨다. 이 혼합물을 3시간 동안40℃의 온도에서 교반시키고 상온으로 냉각시키며 그 전량을 100㎖의 물/얼음 혼합액에 붓고 이를 여과시킨다음, 그 잔류물을 다량의 증류수와 0.5N 염산 및 증류수로 차례로 세척한 후, 이때 얻어진 잔류물을 아세톤에 용해시키면 융점이 259-261℃인 5-메틸-3-(4-메틸피리딘-2-일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온 6,6-디옥사이드 결정을 3.45g(93%) 얻게 된다.3.45 g (0.01 mol) of N- (4-methylpyridin-2-yl) -4-hydroxy-2-methyl-2H-1,2- in a mixture of 2 g 4-dimethylaminopyridine and 25 ml anhydrous pyridine 5 mL (0.04 mole) of phenylchloroformate is added to the partial solution obtained by dissolving benzothiazine-3-carboxamide 1,1-dioxide while stirring at room temperature. The mixture is stirred at a temperature of 40 ° C. for 3 hours, cooled to room temperature, poured into 100 ml of water / ice mixture and filtered, and the residue is washed sequentially with a large amount of distilled water, 0.5N hydrochloric acid and distilled water. The residue thus obtained was dissolved in acetone to give 5-methyl-3- (4-methylpyridin-2-yl) -2H, 5H-1,3-oxazino [5,6] having a melting point of 259-261 ° C. -c] [1,2] benzothiazine-2,4- (3H) -dione 6,6-dioxide crystals yield 3.45 g (93%).
분광테이타Spectral data
IR(KBr) ; 1195 ; 1360 ; 1415 ; 1640 ; 1720 ; 1795cm-1 IR (KBr); 1195; 1360; 1415; 1640; 1720; 1795 cm -1
lH NMR, δ, [DMSO-d6] : 2.42(s,3H) ; 3.10(m,3H) ; 7.40 ; (m,2H) ; 7.98(m,4H) ; 8.40(d,lH) l H NMR, δ, [DMSO -d 6]: 2.42 (s, 3H); 3.10 (m, 3 H); 7.40; (m, 2H); 7.98 (m, 4 H); 8.40 (d, lH)
[실시예 4]Example 4
5-메틸-3-(6-메틸피리딘-2일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온6,6-디옥사이드의 제조5-methyl-3- (6-methylpyridin-2yl) -2H, 5H-1,3-oxazino [5,6-c] [1,2] benzothiazine-2,4- (3H)- Preparation of Dione 6,6-Dioxide
2g의 4-디메틸아미노피리딘과 25㎖의 무수피리딘의 혼합물에 3.45g(0.01몰)의 N-(6-메틸피리딘-2-일)-4-하이드록시-2-메틸-2H-1,2-벤조티아진-3-카복사미드 1,1-디옥사이드를 용해시켜서 된 부분 용액에다 3㎖(0.04몰)의 메틸 클로로포메이트를 교반시키면서 첨가시키되 온도를 계속 10℃ 이하로 유지시키면서 얼음조에서 냉각시킨다. 이 혼합물을 상온에서 30시간 동안 교반시키고 그 전량을 100㎖의 물/얼음 혼합액에 붓고 이를 여과시킨 다음, 그 잔류물을 다량의 중류수와 0.5N 염산 및 증류수로 차례로 세척한 후, 이때 얻어진 잔류물을 아세톤에 용해시키면 융점이 248-250℃인 5-메틸-3-(6-메틸피리딘-2일)-2H,5H-1,3-옥사지노[5,6-c][1,2]벤조티아진-2,4-(3H)-디온6,6-디옥사이드 결정을 3.6g(97%) 얻게된다.3.45 g (0.01 mole) N- (6-methylpyridin-2-yl) -4-hydroxy-2-methyl-2H-1,2 in a mixture of 2 g 4-dimethylaminopyridine and 25 ml anhydrous pyridine To a partial solution of benzothiazine-3-carboxamide 1,1-dioxide, add 3 ml (0.04 mole) of methyl chloroformate with stirring, keeping the temperature below 10 ° C in an ice bath. Cool. The mixture was stirred at room temperature for 30 hours, the whole amount was poured into 100 ml of water / ice mixture and filtered, and the residue was washed sequentially with a large amount of midstream, 0.5N hydrochloric acid and distilled water, and then the residue obtained When water is dissolved in acetone, 5-methyl-3- (6-methylpyridin-2yl) -2H, 5H-1,3-oxazino [5,6-c] [1,2 having a melting point of 248-250 ° C. ] 3.6 g (97%) of benzothiazine-2,4- (3H) -dione 6,6-dioxide crystals are obtained.
분광테이타Spectral data
IR(KBr) ; 1190 ; 1360 ; 1410 ; 1640 ; 1715 ; 1790cm-1 IR (KBr); 1190; 1360; 1410; 1640; 1715; 1790 cm -1
lH NMR, δ, [DMSO-d6] : 2.43(s,3H) ; 3.00(m,3H) ; 7.40(m,2H) ; 7.97(m,5H) l H NMR, δ, [DMSO -d 6]: 2.43 (s, 3H); 3.00 (m, 3 H); 7.40 (m, 2 H); 7.97 (m, 5H)
Claims (7)
Priority Applications (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019870005549A KR900003501B1 (en) | 1987-06-02 | 1987-06-02 | Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives |
Applications Claiming Priority (1)
Application Number | Priority Date | Filing Date | Title |
---|---|---|---|
KR1019870005549A KR900003501B1 (en) | 1987-06-02 | 1987-06-02 | Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives |
Publications (2)
Publication Number | Publication Date |
---|---|
KR890000499A KR890000499A (en) | 1989-03-14 |
KR900003501B1 true KR900003501B1 (en) | 1990-05-21 |
Family
ID=19261878
Family Applications (1)
Application Number | Title | Priority Date | Filing Date |
---|---|---|---|
KR1019870005549A KR900003501B1 (en) | 1987-06-02 | 1987-06-02 | Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives |
Country Status (1)
Country | Link |
---|---|
KR (1) | KR900003501B1 (en) |
-
1987
- 1987-06-02 KR KR1019870005549A patent/KR900003501B1/en not_active IP Right Cessation
Also Published As
Publication number | Publication date |
---|---|
KR890000499A (en) | 1989-03-14 |
Similar Documents
Publication | Publication Date | Title |
---|---|---|
AU2009258496B2 (en) | Sulfur-containing heterocyclic derivative having beta-secretase-inhibiting activity | |
CA1103246A (en) | Thiazine derivatives | |
CA2077919A1 (en) | Process for the preparation of 4- substituted-1, 4-dihydropydrines | |
US4797482A (en) | Process for the preparation of oxazinobenzothiazine 6,6-dioxide derivatives | |
KR900003501B1 (en) | Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives | |
HUT64759A (en) | Method for producing tetrazolyl-(phenoxy-and phenoxy-alkyl-)-pyridinyl-pyridazines | |
US4748280A (en) | Certain chlorination process for preparing 2-chloro-1,1,1-(C1 -C6) | |
SU569291A3 (en) | Method of preparation of thiazoloizoquinoline derivatives or salts thereof | |
US4052394A (en) | 2-(dicyanomethylene)-1,3-dithiolo-(4,5-b)pyrazine-5,6-dicarbonitrile | |
US2650226A (en) | Furo and thieno quinaldines and process for making same | |
KR950009827B1 (en) | Benzothiazine derivatives | |
BRPI0614847A2 (en) | chemical process | |
US4376204A (en) | 3-Hydroxy 2-methyl benzisothiazolines as intermediates in production of piroxicam | |
KR920005746B1 (en) | Process for the preparation of oxazino benzothiazine 6,6-dioxide derivatives | |
KR850001037B1 (en) | Process for 3,4-dihydro-2-substituted-2h-1,2-benzothiazine-carboxylic acid 1,1-dioxide derivatives | |
US4797483A (en) | Process for obtaining 4-hydroxy-2-methyl-N-(2-pyridyl)-2H-1,2-benzothiazine-3-carboxamide 1,1-dioxide | |
US4683306A (en) | Process for the preparation of 3,4-dihydro-2-substituted-2H-1,2-thiazine-carboxylic acid 1,1-dioxide derivatives | |
US4723010A (en) | Process for preparing chloromethyl thiazoles or oxazoles, and intermediates for use therein | |
KR850001223B1 (en) | Process for preparing piroxicam and intermediates leading thereto | |
KR100229175B1 (en) | Process for preparation of cephem derivatives | |
KR920008615B1 (en) | Thiazoline derivatives and its method | |
JPH05339242A (en) | Production of 5-chloro-4-nitropyrazole derivative | |
KR810000717B1 (en) | Process for preparing isoquinoline derivatives | |
US20010039351A1 (en) | Novel process | |
TAKEZAWA et al. | Studies on Mesoionic Compounds. XIV. Synthesis of Mesoionic 1, 3-Thiazolium-4-thiolates |
Legal Events
Date | Code | Title | Description |
---|---|---|---|
A201 | Request for examination | ||
N231 | Notification of change of applicant | ||
G160 | Decision to publish patent application | ||
E701 | Decision to grant or registration of patent right | ||
GRNT | Written decision to grant | ||
FPAY | Annual fee payment |
Payment date: 19970515 Year of fee payment: 8 |
|
LAPS | Lapse due to unpaid annual fee |