Trinuclear Ni3S4N3 clusters were obtained from (1S,2S)-1-monothiasulfato-1-phenyl-2-(methylammoniumyl)propane (tpmp). Three homochiral ligand molecules together with three NiII ions give rise to a cone-shaped cluster topped by a μ3-sulfide ion. Each NiII is in a distorted planar geometry. X-ray structural studies showed that in three cases the three phenyl groups form the rim of a cage which contains R-OSO3 (R=C2H5, C3H 7) or nitrate anions. The alkyl sulfates were generated during the synthesis reaction, and are hydrogen-bonded through the oxygen atoms to the amine nitrogen atoms. The corresponding compound with the methyl sulfate anion (MeOSO3) reacts with FeIII nitrate to form a similar compound in which the nitrate anion occupies the cavity and its crystals were analyzed by X-ray diffraction. © 2004 Elsevier Ltd. All rights reserved.