专利号:US-6995289-B2 优先权日:2000-08-02 标题 :Process for synthesis of alpha, beta-unsaturated ketones 发明人:PATEL IAN; HOPES PHILIP 权利人:ASTRAZENECA AB 摘要:A method for the synthesis of an α,β-unsaturated ketone useful for making substituted 1,4-dihydropyridines is described by reacting an aldehyde with pyrrolidine and then adding a ketone followed by trifluoroacetic acid at low temperature. The synthesis is used in a process for making substituted 1,4-dihydropyridines wherein a vinylogous amide is prepared by reacting a 1,3-cyclohexanedione with a phenylethylamine. The α,β-unsaturated ketone can be reacted with a vinylogous amide to form a 1,5-diketone which can be converted to a substituted 1,4-dihydropyridine.
专利号:US-11008285-B2 优先权日:2017-03-27 标 题 :Process for synthesis of mesotrione 发明人:GHARDA KEKI HORMUSJI; MATHUR SUCHET SARAN; JAIN NANDKUMAR JANARDAN; SATHE SHEKHAR VISHWANATH; DAMANIA PRAGNESH DALPATRAM 权利人:GHARDA CHEMICALS LTD 摘要:The present disclosure relates to a process for synthesis of mesotrione. The process comprises reacting 4-toluene sulfonyl chloride with alkali metal sulphite and alkali metal bicarbonate to obtain alkali metal toluene-4-sulfinate. The alkali metal toluene-4-sulfinate is reacted with alkali metal salt of monochloroacetic acid to obtain 4-methylsulfonyl toluene. Further, 4-methylsulfonyl toluene is nitrated to obtain 2-nitro-4-methylsulfonyl toluene. 2-nitro-4-methylsulfonyl toluene is oxidized and then halogenated to obtain 2-nitro-4-methylsulfonylbenzoyl halide. 2-nitro-4-methylsulfonylbenzoyl halide is reacted with alkali metal salt of 1,3-cyclohexanedione to obtain 3-(2-Nitro-4-methylsulfonylbenzoyloxy)cyclohexen-1-one which is reacted with base, a third fluid medium and cyanide ion source to obtain an amorphous mesotrione. The present disclosure also discloses the steps of converting the amorphous mesotrione to crystalline mesotrione having purity greater than 99%. The process of the present disclosure for preparing mesotrione is rapid, economic, and environment friendly.
专利号:US-4045452-A 优先权日:1974-03-13 标题 :Steroid total synthesis process utilizing a cyanoalkyl A-ring precursor 发明人:COHEN NOAL; ROSENBERGER MICHAEL; SAUCY GABRIEL 权利人:HOFFMANN LA ROCHE 摘要:A multi-step, stereospecific total synthesis of steroids utilizing intermediates having a cyanoalkyl A-ring precursor is disclosed. The initial starting materials for this process are the relatively inexpensive and commercially available reagents γ-butyrolactone and sodium cyanide. The process is suitable for the preparation of racemic or optically active, medicinally valuable steroids, particularly 19-norsteroids. It is a feature of this process that conditions employed during the multiple step synthesis are selected so as to retain the normally labile nitrile group even during hydrogenation and hydrolysis steps. In this manner, it is possible to employ the nitrile group as an A-ring precursor without resorting to protective groups as wasl heretofore found necessary in previous steroid total synthesis processes.
专利号:US-4105676-A 优先权日:1975-12-22 标题 :Steroid total synthesis process utilizing a cyanoalkyl a-ring precursor 发明人:COHEN NOAL; ROSENBERGER MICHAEL; SAUCY GABRIEL 权利人:HOFFMANN LA ROCHE 摘要:A multi-step, stereospecific total synthesis of steroids utilizing intermediates having a cyanoalkyl A-ring precursor is disclosed. The initial starting materials for this process are the relatively inexpensive and commercially available reagents γ-butyrolactone and sodium cyanide. The process is suitable for the preparation of racemic or optically active, medicinally valuable steroids, particularly 19-norsteroids. It is a feature of this process that conditions employed during the multiple step synthesis are selected so as to retain the normally labile nitrile group even during hydrogenation and hydrolysis steps. In this manner, it is possible to employ the nitrile group as an A-ring precursor without resorting to protective groups as was heretofore found necessary in previous steroid total synthesis processes.
专利号:US-3965138-A 优先权日:1974-03-13 标 题:Steroid total synthesis process utilizing a cyanoalkyl A-ring precursor 发明人:COHEN NOAL; ROSENBERGER MICHAEL; SAUCY GABRIEL 权利人:HOFFMANN LA ROCHE 摘要:A multi-step, stereospecific total synthesis of steroids utilizing intermediates having a cyanoalkyl A-ring precursor is disclosed. The initial starting materials for this process are the relatively inexpensive and commercially available reagents γ-butyrolactone and sodium cyanide. The process is suitable for the preparation of racemic or optically active, medicinally valuable steroids, particularly 19-norsteroids. It is a feature of this process that conditions employed during the multiple step synthesis are selected so as to retain the normally labile nitrile group even during hydrogenation and hydrolysis steps. In this manner, it is possible to employ the nitrile group as an A-ring precursor without resorting to protective groups as was heretofore found necessary in previous steroid total synthesis processes.
专利号:US-3991084-A 优先权日:1970-08-26 标题 :Steroid total synthesis process utilizing a cyanoalkyl A-ring precursor 发明人:COHEN NOAL; ROSENBERGER MICHAEL; SAUCY GABRIEL 权利人:HOFFMANN LA ROCHE 摘要:A multi-step, stereospecific total synthesis of steroids utilizing intermediates having a cyanoalkyl A-ring precursor is disclosed. The initial starting materials for this process are the relatively inexpensive and commercially available reagents γ-butyrolactone and sodium cyanide. The process is suitable for the preparation of racemic or optically active, medicinally valuable steroids, particularly 19-norsteroids. It is a feature of this process that conditions employed during the multiple step synthesis are selected so as to retain the normally labile nitrile group even during hydrogenation and hydrolysis steps. In this manner, it is possible to employ the nitrile group as an A-ring precursor without resorting to protective groups as was heretofore found necessary in previous steroid total synthesis processes.
参考文献:10.1107/s1600536811017867 摘要:Mehdi SH, Hashim R, Ghalib RM, Yeap CS, Fun HK. 9-(3,4-Dimeth-oxy-phen-yl)-3,4,5,6,7,9-hexa-hydroxanthene-1,8(2H)-dione. Acta Crystallogr Sect E Struct Rep Online. 2011 Jun 01;67(Pt 6):o1449. 参考文献:10.1016/j.bmc.2011.06.057 摘要:Mwakaboko AS, Zwanenburg B. Single step synthesis of strigolactone analogues from cyclic keto enols, germination stimulants for seeds of parasitic weeds. Bioorg Med Chem. 2011 Aug 15;19(16):5006–11. doi: 10.1016/j.bmc.2011.06.057.