Sankyo Company, Limited

Sebastian Lazareno

Kazuo Koyama

Shinji Marumoto

Syunji Naruto

Nigel Birdsall

A compound of formula (I): ##STR1## wherein Y.sup.1, Y.sup.2, Y.sup.3 and Y.sup.4 are each hydrogen, halogen, nitro, cyano, hydroxyl, thiol, amino, alkyl, haloalkyl, alkylthio, a protected or unprotected carboxyl, a protected or unprotected sulfonamide, or tetrazol; one of R.sup.1 and R.sup.2 is hydrogen, alkyl, aryl, aralkyl, oxazolyl, or a protected or unprotected carboxyl and the other of R.sup.1 and R.sup.2 is hydrogen, alkyl, aryl or aralkyl; and R.sup.3 is hydrogen or an amino protecting group, and pharmaceutically acceptable salts or esters thereof. The compounds are effective for treating dementia, Alzheimer's disease and delirium and are effective as sedatives.

Growing community of inventors

Ware, United Kingdom

Sebastian Lazareno