In the title comound, C8H8N4S, one of the two independent
molecules is essentially planar (r.m.s. deviation = 0.025 A ° ),
while the other is slightly buckled (r.m.s. deviation = 0.131 A ° )
with the guanidine unit bent out of the plane of the fused-ring
system by 16.8 (1). In the crystal, intermolecular N—H N
hydrogen bonds between the two independent molecules give
rise to a hydrogen-bonded dimer. Addtional weak intermolecular
N—H N hydrogen bonds connect these dimers
into chains along [010]. An intramolecular N—H N
hydrogen bond is also observed in each independent molecule.