a compound of the formula ## str1 ## in which r 1 is hydrogen , halogen , lower alkyl , lower alkoxy or trifluoromethyl ; r 2 is hydrogen or lower alkyl having one to three carbon atoms ; and r 5 is benzyl or lower alkyl ; and a compound of the formula ## str2 ## in which r 1 is hydrogen , halogen , lower alkyl , lower alkoxy or trifluoromethyl ; r 2 is hydrogen or lower alkyl having one to three carbon atoms ; and x is bromo or chloro , or hydrogen ; as intermediates for pyrazino pyrido indoles which are useful for treating hypertension in mammals .