A Useful and Environmentally Benign Synthetic Protocol for Dethiolization by Employing Vanadium Pentoxide Catalyzed Oxidation of Ammonium Bromide by Hydrogen Peroxide
作者:Ejabul Mondal、Gopal Bose、Priti Rani Sahu、Abu T. Khan
DOI:10.1246/cl.2001.1158
日期:2001.11
presence of olefin and aromatic ring as well as other protecting groups to carbonyl compounds by employing V2O5 catalyzedoxidation of ammonium bromide by H2O2 in CH2Cl2–H2O solvent system; mild conditions, high selectivity, good yield, and no side products such as bromination or oxidation are some of the major advantages.
A Useful and Catalytic Method for Protection of Carbonyl Compounds into the Corresponding 1,3-Oxathiolanes and Deprotection to the Parent Carbonyl Compounds
作者:Ejabul Mondal、Priti Rani Sahu、Abu T. Khan
DOI:10.1055/s-2002-20466
日期:——
A wide variety of carbonyl compounds 1 can be easily protected to the corresponding 1,3-oxathiolanes 2 in good yields in the presence of catalytic amount of perchloric acid in dry CH2Cl2 at 0-5 °C. On the other hand, various 1,3-oxathiolanes 2 can be selectively deprotected to the parent carbonyl compounds 1 in very good yields by H2MoO4·H2O-H2O2 catalyzed oxidation of ammonium bromide in the presence of perchloric acid in CH2Cl2-H2O solvent system. Mild reaction condition, high selectivity, efficient and relatively good yields are some of the major advantages of the procedure.
Inhibitors of squalene synthetase and protein farnesyltransferase
申请人:Abbott Laboratories
公开号:US05783593A1
公开(公告)日:1998-07-21
The present invention provides a compound of the formula ##STR1## which inhibit squalene synthetase and cholesterol biosynthesis and are useful in the treatment of e.g., hyperlipidaemia, atherosclerosis, or fungal infections, processes for the preparation of the compounds of the invention, intermediates useful in these processes, and pharmaceutical compositions containing the compounds.
A useful and convenient synthetic protocol for interconversion of carbonyl compounds to the corresponding 1,3-oxathiolanes and vice versa employing organic ammonium tribromide (OATB)
作者:Ejabul Mondal、Priti Rani Sahu、Gopal Bose、Abu T. Khan
DOI:10.1016/s0040-4039(02)00345-3
日期:2002.4
A wide variety of carbonyl Compounds I can be easily protected selectively as the corresponding 1.3-oxathiolanes 2 in good yields using a catalytic amount (0.01-0.1 equiv.) of n-tetrabutylammonium tribromide in dry CH2Cl2 at 0-5 degreesC. On the other hand, various 1,3-oxathiolanes 2 can be deprotected chemoselectively to the parent carbonyl compounds I employing 0.5 equivalents of organic ammionum tribromides under identical conditions in verb high yields. Mild conditions, high selectivity and yield, highly efficient. less expensive, and no brominations either at the double bond or allylic position and even alpha- to the keto position or aromatic ring are some of the major advantages of the protocol. (C) 2002 Elsevier Science Ltd. All rights reserved.
CYCLOBUTANE DERIVATIVES AS INHIBITORS OF SQUALENE SYNTHETASE AND PROTEIN FARNESYLTRANSFERASE