A compound or pharmaceutically acceptable salt thereof, which is selected from the group: 1) N -[(1 S)-2,2,5,7-tetrafluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 2) N -[(1 S)-2,2,4,7-tetrafluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 3) (+)- N -(2,2,4,6,7-pentafluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 4) N -[(1 S *)-5-cyano-2,2-difluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfami de, 5) (-)- N -(7-chloro-2,2,5-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 6) (-)- N -(7-chloro-2,2,4-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 7) (-)- N -(7-chloro-2,2-difluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 8) (-)- N -(7-chloro-2,2,6-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 9) (+)- N -(5-chloro-2,2,7-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 10) N -[(1 S)-2,2-difluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 11) N -[ -2,2,5-trifluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 12) N -[(1S*)-2,2,4-trifluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 13) N -[(1S*)-7-(difluoromethyl)-2,2-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfa mide, 14) N -[(1 R *,2 R *)-2,4,7-trifluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 15) (-)- N -[(1 R *,2 R *)-7-chloro-2,4-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 16) (+)- N -[(1 R *,2 R *)-7-chloro-2,4-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 17) (-)- N -[(1 R *,2 R *)-7-chloro-2,5-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 18) (+)- N -[(1 R *,2 R *)-4-chloro-7-fluoro-2-methoxy-2,3-dihydro-1 H -inden-1-yl] sulfamide, 19) (+)- N -(7-chloro-4-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 20) (±)- N -(5-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 21) (-)- N -(4-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 22) (+)- N -(4-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 23) (+)- N -(7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 24) (±)- N -(5-chloro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 25) (-)- N -(4-chloro-7-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 26) (+)- N -(7-chloro-5-cyano-2,3-dihydro-1 H -inden-1-yl)sulfamide, 27) (-)- N -(7-chloro-5-cyano-2,3-dihydro-1 H -inden-1-yl)sulfamide, 28) (-)- N -(5-chloro-7-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 29) N-[(1 S)-4,7-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 30) (+)- N -(7-chloro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 31) (+)- N -(5-cyano-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 32) (-)- N -(5-cyano-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 33) N -[(1 S)-7-chloro-5-fluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide and 34) (-)- N -(4,6,7-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide. 1) N -[(1 S)-2,2,5,7-tetrafluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 2) N -[(1 S)-2,2,4,7-tetrafluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 3) (+)- N -(2,2,4,6,7-pentafluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 4) N -[(1 S *)-5-cyano-2,2-difluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfami de, 5) (-)- N -(7-chloro-2,2,5-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 6) (-)- N -(7-chloro-2,2,4-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 7) (-)- N -(7-chloro-2,2-difluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 8) (-)- N -(7-chloro-2,2,6-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 9) (+)- N -(5-chloro-2,2,7-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 10) N -[(1 S)-2,2-difluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 11) N -[ -2,2,5-trifluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 12) N -[(1S*)-2,2,4-trifluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl]sulfamide, 13) N -[(1S*)-7-(difluoromethyl)-2,2-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfa mide, 14) N -[(1 R *,2 R *)-2,4,7-trifluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 15) (-)- N -[(1 R *,2 R *)-7-chloro-2,4-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 16) (+)- N -[(1 R *,2 R *)-7-chloro-2,4-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 17) (-)- N -[(1 R *,2 R *)-7-chloro-2,5-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfami de, 18) (+)- N -[(1 R *,2 R *)-4-chloro-7-fluoro-2-methoxy-2,3-dihydro-1 H -inden-1-yl] sulfamide, 19) (+)- N -(7-chloro-4-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 20) (±)- N -(5-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 21) (-)- N -(4-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 22) (+)- N -(4-fluoro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 23) (+)- N -(7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 24) (±)- N -(5-chloro-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 25) (-)- N -(4-chloro-7-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 26) (+)- N -(7-chloro-5-cyano-2,3-dihydro-1 H -inden-1-yl)sulfamide, 27) (-)- N -(7-chloro-5-cyano-2,3-dihydro-1 H -inden-1-yl)sulfamide, 28) (-)- N -(5-chloro-7-fluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 29) N-[(1 S)-4,7-difluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide, 30) (+)- N -(7-chloro-2,3-dihydro-1 H -inden-1-yl)sulfamide, 31) (+)- N -(5-cyano-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 32) (-)- N -(5-cyano-7-methyl-2,3-dihydro-1 H -inden-1-yl)sulfamide, 33) N -[(1 S)-7-chloro-5-fluoro-2,3-dihydro-1 H -inden-1-yl]sulfamide and 34) (-)- N -(4,6,7-trifluoro-2,3-dihydro-1 H -inden-1-yl)sulfamide.