Heterocyclische Verbindungen aus Zuckern, XV: Zur Konfiguration chiraler C-2-substituierter 4-Thiazolidincarbons�uren. Chiralit�tstransfer auf C-3 in 3,4-Dihydro-1H-pyrrolo[1,2-c]thiazolen
摘要:
5-Substituted 3,4-dihydro-pyrrolo[1,2-c]thiazole-6,7-dicarboxylic acid esters 3 are obtained from 2-substituted-3-acyl-1,3-thiazolidine-4-carboxylic acids, 1 in [3 + 2]-cycloaddition reactions via mesoionic oxazolone (''munchnone'') intermediates. The chirality at C-4 of the starting carboxylic acids 1 is eliminated in the products 3, and the chirality at C-3 (C-2 in the starting carboxylic acids 1) can thus be determined through chiroptical measurements. Several representatives of the ring system 3 have been characterised through H-1- and CD-spectra and the molecular structure of (3S)-3da has been determined by X-ray crystallography.
N-terminal D(-)-penicillamine peptides as aldehyde sequestration agents
申请人:——
公开号:US20010041789A1
公开(公告)日:2001-11-15
The invention provides a compound of formula I:
1
wherein R
1
-R
3
have any of the values described in the specification; or a salt thereof. The compounds are useful as aldehyde sequestration agents (e.g., in the treatment of alcohol-related diseases). The invention also provides compositions comprising such compounds as well as therapeutic methods comprising their administration.
Bioadhesives coatings increase the gastrointestinal retention time of orally-ingested medicaments. Certain bioadhesive coatings producing a fracture strength of at least 100 N/m
2
, as measured on rat intestine, when applied to at least one surface of a pharmaceutical dosage form for oral delivery of a drug, result in a gastrointestinal retention time of at least 4 hours in a fed beagle dog model, during which the drug is released from the dosage form.
Multi-layer tablets, particularly those including hydrophobic excipients, are useful in administering hygroscopic and/or deliquescent drugs. In addition, varying the amount of drug in multi-layer tablets allows the release rate of the drug to be controlled.
Verfahren zur Ringspaltung von in 4-Stellung substituierten 2-Isopropyl-5,5-dimtehylthiazolidinen
申请人:Degussa Aktiengesellschaft
公开号:EP0235376A2
公开(公告)日:1987-09-09
Die Erfindung betrifft ein Verfahren zur Ringspaltung von in 4-Stellung substituierten 2-Isopropyl-5,5-dimethylthiazolidinen in wässrigem, saurem Medium bei erhöhter Temperatur.
Ist der Fünfring in 4-Stellung durch eine Carboxylgruppe substituiert, entsteht Penicillamin.
Described herein is a cast-molding process for producing contact lenses in a relatively short curing time. The short curing time has been achieved by adding a chain transfer agent into a lens-forming composition.
Cast-molding process for producing UV-absorbing contact lenses
申请人:Novartis AG
公开号:US11111327B2
公开(公告)日:2021-09-07
Described herein is a cast-molding process for producing contact lenses in a relatively-short curing time from a lens-forming composition, which comprises (a) at least one thiol-containing compound or component, (b) at least one metal scavenger, and (c) at least one free radical scavenger and which has a pH of from about 2.5 to about 5. The addition of a chain-transfer agent into a lens-forming composition can reduce not only the curing time of the lens-forming composition but also reduce the elastic modulus of resultant crosslinked materials (e.g., contact lenses) from the lens-forming composition. The lower pH and the addition of metal scavenger and the free radical scavenger into the lens-forming composition can ensure that the lens-forming composition to have a shelf life of at least three days.