Condensation of 2-thioxo-2,3-dihydro-1 H -spiro[benzo[ h ]quinazoline-5,1′-cycloheptane]-4(6 H )-one with hydrazine hydrate afforded 2-hydrazinyl-3 H -spiro[benzo[ h ]quinazoline-5,1′-cycloheptane]-4(6 H )-one. The reaction of the latter with orthoformic acid ethyl ester or carbon disulfide yielded 5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ]quinazoline-6,1′-cycloheptane]-7(11 H )-one and 9-mercapto-5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ] quinazoline-6,1 ‘-cycloheptane]-7(11 H )-one, respectively. Alkylation of the latter with methyl and ethyl iodides, allyl bromide, and benzyl chloride gave 9-sulfanyl-substituted 5 H -spiro[benzo[ h ][1,2,4]triazolo[3,4- b ]quinazoline-6,1′-cycloheptane]-7(11 H )-ones. The synthesized compounds exhibited antibacterial properties.