A naphthopyran compound of general formula (I) ##STR1## wherein R.sub.1 represents an alkyl group or an aryl group; each of R.sub.4 and R.sub.5, which may be the same or different, independently represents an alkyl, alkenyl, carbocyclic or heterocyclic group, or R.sub.4 and R.sub.5 taken together with the carbon atom to which they are attached form a carbocyclic ring or a heterocyclic ring; and R.sub.6 represents a hydrogen atom or a substituent selected from alkyl, alkoxy, aryl, aryloxy, heteroaryl, halogen, amino, substituted amino, azo, imino, amide, carboxylate, ester, cyano, trifluromethyl or nitro, and in addition R.sub.6 may represent a carbocyciic or heterocyclic ring fused to ring A. The naphthopyran compounds of the invention are useful as photochromic materials in lenses, e.g. sunglasses, and photochromic transparencies for cars and aircraft.
Lewis-Acid-Mediated Intramolecular Trifluoromethylthiolation of Alkenes with Phenols: Access to SCF<sub>3</sub>-Containing Chromane and Dihydrobenzofuran Compounds
A Lewis-acid-mediated intramolecular trifluoromethylthiolation of alkenes with phenols that can offer direct access to SCF3-containing chromane and dihydrobenzofuran compounds was disclosed for the first time. Numerous SCF3-containing chromanes were obtained in moderate to good yields using γ-substituted 2-allyphenols as substrates. Meanwhile, various SCF3-containing dihydrobenzofurans with oxa-quaternary
An acid-promoted multicomponent reaction for the synthesis of diverse fully substituted oxazole derivatives from simple and readily available arylglyoxal monohydrates, nitriles, and various C-nucleophiles has been developed. This protocol features wide functional group diversity which is capable of installing 4-hydroxycoumarin, 2-naphthol, and 1,3-cyclohexanedione motifs to oxazoles. Mechanistic analysis
Described herein is the Ir-catalyzed enantioselective access to chiral spirolactam products via the nitrenoidtransfer to aromatic ipso-carbons. The key strategy for precise stereocontrol is to enhance the secondary attractive and repulsive interactions between the chiral catalyst and substrates by the introduction of a traceless O-silyl achiral auxiliary, thus effectively differentiating two prochiral
[EN] EFFLUX PUMP INHIBITORS<br/>[FR] INHIBITEURS DE POMPE D'ECOULEMENT
申请人:MICROCIDE PHARMACEUTICALS, INC.
公开号:WO1999037667A1
公开(公告)日:1999-07-29
(EN) Compounds are described which have efflux pump inhibitor activity. Also described are methods of using such efflux pump inhibitor compounds and pharmaceutical compositions which include such compounds.(FR) L'invention concerne des composés présentant une activité d'inhibiteur de pompe d'écoulement. L'invention concerne également des méthodes d'utilisation de ces composés inhibiteurs et des compositions pharmaceutiques renfermant de tels composés.