| abstract |
1,4-Oxazine tetracyclic derivatives of formula (I) and their acid addition salts in racemic, optically active or enantiomeric forms are new. X, Y = O or CH2; A-B = -(CH2)2- or -HC=CH-, and when Y = O, then A-B may also be -(CH2)3-, when Y = CH2 then A-B may also be -H2C-CO- or -H2C-CHOH-; R = H, 1-10C alkyl, 3-10C alkenyl, 3-10C alkynyl, all of which opt. substd. by 3-8C cycloalkyl, or by phenyl, thienyl, and pyridyl, each of which may be substd. by one or more halogens, OH, or 1-6C alkyl or alkoxy; n = 0 or 1 when X = CH2, or is 1 when X = O. |