# US 4,398,028 A · Bicyclic heterocyclic amino derivatives > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 4,398,028 A - Document ID: US4398028A - Status: Granted - Kind: A - Application number: 06/277,054 - Filed: 1981-06-24 - Granted: 1983-08-09 - Earliest claimed: 1978-01-13 - Assignees: Sandoz Ltd. - Inventors: Peter Neumann - Web page: https://patentgrep.com/patent/US4398028A ## CPC - C07D 307/79: with only hydrogen atoms, hydrocarbon or substituted hydrocarbon radicals, directly attached to carbon atoms of the hetero ring - C07D 271/08: 1,2,5-Oxadiazoles; Hydrogenated 1,2,5-oxadiazoles - C07D: HETEROCYCLIC COMPOUNDS (macromolecular compounds C08) ## Abstract The present invention concerns compounds of formula ##STR1## wherein X is O, S or NH; n is 1 or 2 and A is a 5-membered heterocyclic ring, wherein the bicyclic system may be substituted. The compounds are useful as myotonolytic and anti-hypertensive agents. ## Claims ### Claim 1 A compound having the formula ##STR6## wherein the heterocyclic amino moiety is bonded to the benzene ring of the bicyclic moiety, n is an integer 1 or 2, R.sub.1, which is bonded to the benzene ring of the bicyclic moiety, is hydrogen, halo, C.sub.1-4 -alkyl, C.sub.1-4 alkylthio, C.sub.1-4 alkoxy, trifluoromethyl or hydroxy, A is a five-membered heterocyclic ring selected from the group consisting of [b]pyrrole, [c]pyrrole, [d]triazole, [b]furan, [c]furan, [c]furazan, [d](1,2,3)-thiadiazole, [b]pyrroline, [c]pyrroline, [b]dihydrofuran, [c]dihydrofuran, [b]dihydrothiophene, [c]isoxazole and [d]isoxazole, R.sub.2, which is bonded to the A ring of the bicyclic moiety and attached to a carbon atom of said ring, is hydrogen, halo, C.sub.1-4 alkyl, C.sub.1-4 alkoxy, C.sub.1-4 alkylthio, trifluoromethyl or hydroxy, and R.sub.3, which is bonded to the A ring of the bicyclic moiety and attached to a nitrogen atom of said ring, is hydrogen or C.sub.1-4 alkyl, with the proviso that when A is [c]pyrrole, the nitrogen atom of said pyrrole ring is C.sub.1-4 alkylsubstituted, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 2 (depends on 1) A compound according to claim 1 wherein A is [b]pyrrole, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 3 (depends on 2) A compound according to claim 2 wherein the heterocyclic amino moiety is bonded to the 4- or 7-position of the bicyclic moiety, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 4 (depends on 3) The compound according to claim 3 which is 4-(2-imidazolin-2-yl)amino-benzo[b]pyrrole. ### Claim 5 (depends on 3) The compound according to claim 3 which is 7-(2-imidazolin-2-yl)amino-benzo[b]pyrrole. ### Claim 6 (depends on 3) The compound according to claim 3 which is 7-(2-imidazolin-2-yl)amino-1-methyl-benzo[b]pyrrole. ### Claim 7 (depends on 1) A compound according to claim 1 wherein A is [d]triazole, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 8 (depends on 7) A compound according to claim 7 wherein the heterocyclic amino moiety is bonded to the 4- or 7-position of the bicyclic moiety, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 9 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-2-yl)amino-benzo[d]triazole. ### Claim 10 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-2-yl)amino-5-methyl-benzo[d]triazole. ### Claim 11 (depends on 8) The compound according to claim 8 which is 5-chloro-4-(2-imidazolin-2-yl)amino-benzo[d]triazole. ### Claim 12 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-b 2-yl)amino-1-methyl-benzo[d]triazole. ### Claim 13 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-2-yl)amino-5-methoxy-1-methyl-benzo[d]triazole. ### Claim 14 (depends on 8) The compound according to claim 8 which is 5-chloro-4-(2-imidazolin-2-yl)amino-1-methyl-benzo[d]triazole. ### Claim 15 (depends on 8) The compound according to claim 8 which is 7-(2-imidazolin-2-yl)amino-1-methyl-benzo[d]triazole. ### Claim 16 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-2-yl)amino-2-methyl-benzo[d]triazole. ### Claim 17 (depends on 8) The compound according to claim 8 which is 4-(2-imidazolin-2-yl)amino-5-methoxy-2-methyl-benzo[d]triazole. ### Claim 18 (depends on 8) The compound according to claim 8 which is 5-chloro-4-(2-imidazolin-2-yl)amino-2-methyl-benzo[d]triazole. ### Claim 19 (depends on 8) The compound according to claim 8 which is 1-methyl-7-([3,4,5,6-tetrahydropyrimidin-2-yl]amino)-benzo[d]triazole. ### Claim 20 (depends on 8) The compound according to claim 8 which is 2-methyl-4-([3,4,5,6-tetrahydropyrimidin-2-yl]amino)-benzo[d]triazole. ### Claim 21 (depends on 1) A compound according to claim 1 wherein A is [b]furan, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 22 (depends on 21) A compound according to claim 21 wherein the heterocyclic amino moiety is bonded to the 4- or 7-position of the bicyclic moiety, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 23 (depends on 22) The compound according to claim 22 which is 7-(2-imidazolin-2-yl)amino-benzo[b]furan. ### Claim 24 (depends on 1) A compound acccording to claim 1 wherein A is [d](1,2,3)-thiadiazole, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 25 (depends on 24) The compound according to claim 24 which is 6-chloro-7-(2-imidazolin-b 2-yl)amino-benzo[d](1,2,3)-thiadiazole. ### Claim 26 (depends on 1) A compound according to claim 1 wherein A is [c]furazan, said compound being in free base or in pharmaceutically acceptable acid addition salt form. ### Claim 27 (depends on 26) The compound according to claim 26 which is 4-(2-imidazolin-2-yl)amino-5-methyl-benzo[c]furazan. ### Claim 28 (depends on 26) The compound according to claim 26 which is 4-(2-imidazolin-2-yl)amino-benzo[c]furazan. ### Claim 29 (depends on 26) The compound according to claim 26 which is 4-(2-imidazolin-2-yl)amino-5-methoxy-benzo[c]furazan. ### Claim 30 (depends on 26) The compound according to claim 26 which is 5-chloro-4-(2-imidazolin-2-yl)amino-benzo[c]furazan. ### Claim 31 (depends on 26) The compound according to claim 26 which is 5-(2-imidazolin-2-yl)amino-benzo[c]furazan. ### Claim 32 (depends on 26) The compound according to claim 26 which is 7-chloro-4-(2-imidazolin-2-yl)amino-benzo[c]furazan. ### Claim 33 (depends on 26) The compound according to claim 26 which is 4-bromo-5-(2-imidazolin-2-yl)amino-benzo[c]furazan.