The synthesis physical nature and spectroscopic characterization of several phthaloylamino acids (ligands) have been carried out. Initially, series of two different types of complexes are produced i.e. A-type: Monomeric dibutyltin diphthaloyl-N-carboxylates with 2:1 molar ratio of general formula C6H4(CO)2NRCOO]2SnBu2, B-type: Dimcric tetraorgano dibutyl distannoxane diphthaloyl-N-carboxylates with 1:1 molar ratio of general formula {C6H4(CO)2NRCOO-SnBu2}2O]2 Where R = -CH2,-C2H4, -C4H7, -C5H9, -C2H3C6 H5, -C2H3 C6H5OH. They are characterized by CHN analyzer, FTIR, 1H-, 13i, l19Sn-multinuclear FTNMR and Mssbauer Spectrometer. The monomeric dibutyltin diphthaloyl-N-Carboxylates complexes behave as hexa- coordinate and possess trans octahedral geometry. The dimeric tetraorgano dibutyl distannoxane diphthaloyl carboxylate complexes have penta coordinate environment with a pair of exo- and endo-cyclic structure having fluxional behavior of organic moieties. It is found that most of the mono and dimeric compounds are biocidally active as well as the triorgano- tins show high biocidal activity against various bacteria and fungi.