Abstract: Novel compounds and their salts are disclosed having the Formulas: ##STR1## wherein: R.sub.1 is hydrogen, phenyl, 9H-fluoren-9-yl, 10,11-dihydro-5H-dibenzo [a,d]cyclohepten-5-yl, 5H-dibenzo[a,d]cyclohepten-5-yl, 1,2,3,4-tetrahydro-1-naphthyl, 9H-xanthen-9-yl, 9H-thioxanthen-9-yl, 2-chloro-9H-thioxanthen-9-yl, 4H-chromanyl, diphenylmethyl, phenylcycloalkylmethyl wherein the bridgehead methylene may optionally be substituted with a hydroxy group and any of the phenyl or benzo-fused rings may be substituted with one or more R.sub.5 groups wherein R.sub.5 is selected from halogen, trifluoromethyl, lower alkyl, hydroxy or lower alkoxy groups; andR.sub.2 and R.sub.3, which may be the same or different, are hydrogen, lower alkyl, phenylalkyl (C.sub.1 -C.sub.5), wherein the phenyl ring may be substituted with one or more R.sub.5 groups or NR.sub.2 R.sub.