摘要:
The present invention provides a process for preparing a highly pure form of malathion having a reduced level of toxic impurities. In addition, the malathion prepared by the process of this invention is storage stable. The level of toxic impurities in the malathion, e.g., isomalathion, O,O,S-trimethyl phosphorodithioate (MeOOSPS), O,O,S-trimethyl phosphorothioate (MeOOSPO), O,S,S-trimethyl phosphorodithioate (MeOSSPO), malaoxon, isomalathion, diethyl fumarate, methyl malathion, dimethyl malathion, O,O-methyl,ethyl-S-(1,2-dicarboethoxy)ethyl-phosphorodithioate are lower than that of any other commercial preparation of malathion that may be used for pharmaceutical purposes.
摘要:
The present invention provides a process for preparing a highly pure form of malathion having a reduced level of toxic impurities. In addition, the malathion prepared by the process of this invention is storage stable. The level of toxic impurities in the malathion, e.g., isomalathion, O,O,S-trimethyl phosphorodithioate (MeOOSPS), O,O,S-trimethyl phosphorothioate (MeOOSPO), O,S,S-trimethyl phosphorodithioate (MeOSSPO), malaoxon, isomalathion, diethyl fumarate, methyl malathion, dimethyl malathion, O,O-methyl,ethyl-S-(1,2-dicarboethoxy)ethyl-phosphorodithioate are lower than that of any other commercial preparation of malathion that may be used for pharmaceutical purposes.
摘要:
The present invention provides a method of preparing a 5H-dibenz[b,f]azepine-5-carboxamide of formula (1) wherein R1, R2, R3, and R4 are independently selected from the group consisting of hydrogen, halogen, nitro, cyano, carboxyl, A, —CO(A), —OCO(A), —O(A), —N(A)2, —CON(A)2, and —COO(A), wherein A is selected from the group consisting of C1-C10 alkyl, C3-C10 cycloalkyl, C2-C10 alkenyl, C5-C10 cycloalkenyl, C2-C10 alkynyl, and C6-C20 aryl, wherein the two A groups of —N(A)2 and —CON(A)2 can be the same or different, and wherein R2 and R3 can together form a bond; comprising reacting a 5H-dibenz[b,f]azepine of formula (2) with a) a cyanate salt selected from the group consisting of alkali metal cyanate salts and alkaline-earth metal cyanate salts, and b) a salt of an amino compound having no N—H bonds, wherein the salt has a Ka (25° C.) of at least about 10×10−11.
摘要:
The present invention provides a novel process for preparing 1-methoxymethyl-5,5-diphenylbarbituric acid. In particular, the present invention provides a process for preparing 1-methoxymethyl-5,5-diphenylbarbituric acid by reacting 1,3-bis(methoxymethyl)-5,5-diphenylbarbituric acid with a Lewis acid to selectively remove one methoxymethyl group from 1,3-bis(methoxymethyl)-5,5-diphenylbarbituric acid.
摘要:
The present invention provides a process for preparing a crystalline form of halobetasol propionate, comprising the step of crystallizing halobetasol propionate from absolute ethanol or a mixture of ethanol and water, wherein the crystalline form of halobetasol propionate is characterized by an x-ray powder diffraction pattern having peaks at 10.0, 11.6, 12.9, 13.4, 14.5, 16.4, 17.6, and 23.5±0.2 degrees 2θ.
摘要:
The present invention provides a novel process for preparing 1-methoxymethyl-5,5-diphenylbarbituric acid. In particular, the present invention provides a process for preparing 1-methoxymethyl-5,5-diphenylbarbituric acid by reacting 1,3-bis(methoxymethyl)-5,5-diphenylbarbituric acid with a Lewis acid to selectively remove one methoxymethyl group from 1,3-bis(methoxymethyl)-5,5-diphenylbarbituric acid.
摘要:
A method for producing a 6α-fluorinated corticosteroid or derivative thereof by reacting a 17-hydroxy-21-ester epoxide of Formula II with a stereoselective fluorinating agent to stereoselectively form a 21-ester-17-hydroxy 6α-fluorinated compound of Formula VII R1 can be OC(O)—Rd; R4 can be C(O)—Rd; R3 can be H or Rd. Each Rd may be the same or different and is independently selected from (C1-4)alkyl, aryl and heteroaryl. The dashed line can be a single or a double bond. R4 may be, for example, acetyl; R3 may be, for example, alpha or beta methyl; R1 may be, for example, acetate or propionate, The stereoselective fluorinating agent used in the reaction may be, for example, a fluoropyridinium or fluoroquinuclidium compound, for example, Selectfluor®.
摘要翻译:通过使式II的17-羟基-12-酯环氧化物与立体选择性氟化剂反应来立体选择性地形成式VII R的21-酯-17-羟基6α-氟化化合物来制备6α-氟化皮质类固醇或其衍生物的方法 -R 1可以是OC(O)-R d。 R 4可以是C(O)-R d; R 3可以是H或R d。 每个R d可以相同或不同,并且独立地选自(C 1-4烷基)烷基,芳基和杂芳基。 虚线可以是单键或双键。 R 4可以是例如乙酰基; R 3可以是例如α或β甲基; R 1可以是例如乙酸酯或丙酸酯。反应中使用的立体选择性氟化剂可以是例如氟代吡啶鎓或氟喹喔啉化合物,例如Selectfluor。
摘要:
The present invention provides a method of preparing a 5H-dibenz[b,f]azepine-5-carboxamide of formula (1) wherein R1, R2, R3, and R4 are independently selected from the group consisting of hydrogen, halogen, nitro, cyano, carboxyl, A, —CO(A), —OCO(A), —O(A), —N(A)2, —CON(A)2, and —COO(A), wherein A is selected from the group consisting of C1–C10 alkyl, C3–C10 cycloalkyl, C2–C10 alkenyl, C5–C10 cycloalkenyl, C2–C10 alkynyl, and C6–C20 aryl, wherein the two A groups of —N(A)2 and —CON(A)2 can be the same or different, and wherein R2 and R3 can together form a bond; comprising reacting a 5H-dibenz[b,f]azepine of formula (2) with a) a cyanate salt selected from the group consisting of alkali metal cyanate salts and alkaline-earth metal cyanate salts, and b) a salt of an amino compound having no N—H bonds, wherein the salt has a Ka (25° C.) of at least about 10×10−11.
摘要:
The present invention provides a process of preparing a crystalline azithromycin monohydrate. The process involves dissolving azithromycin in a solution containing ethanol, adding the dissolved azithromycin into water to precipitate the crystals, isolating and drying the precipitate to a water content of about 5% (w/w) to about 7% (w/w). The resulting azithromycin monohydrate is stable, exhibiting less than 2% degradation, and non-hydroscopic.
摘要:
The present invention provides a rapid, high-yielding process for preparing 1,2,3,9-tetrahydro-9-methyl-3-methylene-4H-carbazol-4-one from 1,2,3,9-tetrahydro-9-methyl-4H-carbazol-4-one without using a secondary amine as a catalyst, and without using glacial acetic acid as a solvent. The present invention further provides a rapid, high-yielding process for preparing ondansetron from 1,2,3,9-tetrahydro-9-methyl-3-methylene-4H-carbazol-4-one without using alumina as a catalyst.