unstable thiocyanates. Organic thiocyanates and nitriles are converted efficiently into the corresponding 5-substituted 1H-tetrazoles by treatment with zinc(II) chloride and sodium azide in aliphatic alcohols. The presented procedure provides mild reaction conditions, short reaction times, and good to excellent yields for a wide range of substrates, including deactivated aliphatic nitriles and thermally unstable
Glycoclusters and their pharmaceutical use as antibacterials
申请人:Centre National de la Recherche Scientifique
(CNRS)
公开号:EP2851371A1
公开(公告)日:2015-03-25
A molecule responding to formula (I) of the glycocluster type with galactose residues at their extremities.
Simple and efficient methods for the preparation of these compounds. Medical use of compounds (I) as inhibitors of infections by Pseudomonas aeruginosa, more specifically as inhibitors of Pseudomonas aeruginosa's virulence.
[EN] PROCESS FOR THE PREPARATION OF CALCIPOTRIOL<br/>[FR] PROCÉDÉ POUR LA PRÉPARATION DE CALCIPOTRIOL
申请人:INST FARMACEUTYCZNY
公开号:WO2009008754A2
公开(公告)日:2009-01-15
Process comprising the step of reacting a C-22 phenylsulphonyl derivative of cholecalciferol of Formula (2), wherein R1 and R2 are the same or different and represent hydroxyl protecting groups, with a silyl derivative of alfa-hydroxy aldehyde of Formula (3), wherein R3 represents silyl group of formula Si(R4) (R5)(R6), where R4-R6 are the same or different and represent C1-6 alkyl or phenyl groups, in the presence of a strong organic base in aprotic solvent, followed by a reductive desulfonation of the diastereomeric mixture of alfa- hydroxysulfones with sodium amalgam, removing the hydroxyl protecting groups, and purification, leads to calcipotriol containing less than 0,3% of (22Z)-isomer and free of mercury traces.
Masked development/image modifier compounds of silver photographic
申请人:E. I. Du Pont de Nemours and Company
公开号:US04343893A1
公开(公告)日:1982-08-10
Novel nitrobenzyl compounds are incorporated into a photographic emulsion or developer for controlled release of development/image modifier compounds. This occurs imagewise only after developer oxidation products have been formed in the course of the development process. For example, nitrobenzyl-masked phenylmercaptotetrazole (PMT), incorporated into a silver halide emulsion, reacts with developer oxidation products via an electron transfer mechanism to release the potent development restrainer PMT.