3-(2-Propynyl)-1,2,3,3a,4,5-hexahydrocanthin-6-one hydrochloride 67877-77-4 6H-Indolo(3,2,1-de)(1,5)naphthyridin-6-one, 1,2,3,3a,4,5-hexahydro-3-(2-propynyl)-, monohydrochloride