Tin-119, nitrogen-15, carbon-13, and proton NMR spectroscopy has been used to study the structures of the triorganotin(IV) 8-quinolinethiolates R3Sn(txin) and the diorganotin(IV) di(8-quinolinethiolates) R2Sn(txin)2, (txinH8-quinolinethiol; Rn-butyl, benzyl, phenyl or vinyl) in solutions of non-coordinating (deuteriochloroform) and coordinating (pyridine) solvents. Both types of compounds form molecular chelates having a weak SnN bond in solution. The molecules of R3Sn(txin) and R2Sn(txin)2 complex either form a distorted trigonal bipyramid or a distorted octahedron; the organic substituents R are incis-skew positions. The strength of the SnN and SnO bonds and the degree of the distortion of coordination polyhedra of the compounds studied depend strongly on their composition, i.e. on the number and character of organic substituents R, w hereas the type of solvent plays only a secondary role.