| 摘要 |
<p>NEW MATERIAL:A compound expressed by formula I (R is H, hydroxymethyl or carboxyl; n is an integer 0 or 1), ester and salt thereof. EXAMPLE:beta-( 2,3-Dihydro-6-hydroxy-2,5,7,8-tetramethyl-H-benzopyran-2-y l)alanine hydrochloride. USE:An analgesic agent, having better analgesic action than aspirin with high safety. The agent is administered particularly preferably by oral routes or intravenous injection, and the dose thereof is preferably 100-500mg/day for adults. PREPARATION:An aldehyde expressed by formula II (R' is H or protecting group of OH) is reacted with ammonium carbonate and an alkali metal cyanide, e.g. sodium cyanide, to give a hydantoin expressed by formula III, which is then hydrolyzed to afford the aimed compound expressed by formula I (R is COOH).</p> |
