Ethycellulose microcapsules, wherein a polymer material which shows at least 1.2 times increase in weight by immersing it in water at 37°C is incorporated into the ethylcellulose coating walls and/or the core material thereof, are disclosed. Said ethylcellulose microcapsules show rapid release of the core material in digestive organs such as stomach.
UTILISATION COMME EPAISSISSANTS EN COSMETIQUE DE COPOLYMERES NEUTRALISES COMPORTANT DES MOTIFS D'ACIDE FAIBLE ET DES MOTIFS D'ACIDE FORT
申请人:SNF
公开号:EP1296640B1
公开(公告)日:2009-06-03
US4462982A
申请人:——
公开号:US4462982A
公开(公告)日:1984-07-31
Studies directed toward the total synthesis of tetronolide 2. A stereoselective route to the racemic cyclohexene subunit
作者:Robert K. Boeckman、Kimberly G. Estep、Scott G. Nelson、Michael A. Walters
DOI:10.1016/s0040-4039(00)79872-8
日期:1991.8
A short stereoselective sequence is described for the preparation of the racemic form of the highly functionalized cyclohexene derivative 2 which comprises the upper segment of tetronolide (1), the aglycone of the antitumor tetrocarcins. A key element of this route is rapid assembly and intramolecular cycloaddition of the trienyl enol pyruvate 4, which achieves complete control over regiochemistry