1,2-Bis(ethoxycarbonylmethoxy) benzene undergoes 1 : 1 stoichiometric condensation with 1,2diaminoethane, 1,3-diaminopropane, diethylenetriamine and 3,3'-diaminodipropylamine to form the macrocycles 2a, 2b, 3a and 4a respectively. Methyl iodide, ethyl bromoacetate and chloro-N,Ndiethylacetamide react with triamines 3a and 4a to give the respective N-substituted macrocycles 3b-d and 4b-d. Among these macrocycles, compounds 3a and 4a selectively extract lead picrate over silver, alkali metal and alkaline earth metal picrates and the former shows a higher order of specificity. IR and 13C NMR studies depict a preferential co-ordination of the amide oxygen of these macrocycles with metal ions.Paper 2/03751C

A three step efficient strategy for the synthesis of substituted 5-nitropiperidones in high de, employing Michael addition of N-p-tolylsulfinyl beta-nitroamines to alpha,beta-unsaturated esters, hydrolysis of the sulfinyl group, and cyclization of the resulting free amines, has been developed. A very simple experimental procedure involving mild conditions and only one chromatographic purification are the main features of the process.

Under appropriate reaction conditions, unsymmetrical organosilicon dihalides with two different a I k\ I or aryl groups react with sodium salts of higher cyclic alcohols, viz: cyclopentanol (CyPH). cylohexanol (CyHxH), cyloheptanol (CyHpH) and cyclooctanol (CyOcH). The chloride replacement reaction of these compounds yields complexes of the type PhRSiCl(L) and PhRSi(L) 2 (where L = deprotonated anion of the cyclic alcohol). These novel compounds have been characterized on the basis of elemental anlaysis. IR. 'H NMR, n C NMR and 29 Si NMR spectroscopy. The results of antimicrobial effects of some representative complexes on different species of pathogenic fungi and bacteria have also been recorded. The sterilizing power on male rats has been tested and discussed with positive findings.

The present study deals with a brief description of antifertility and antimicrobial aspects along with the spectral characterization of lead(IV) complexes. The testicular sperm density, testicular sperm morphology, sperm motility, density of cauda epididymal spermatozoa and fertility in mating trails and biochemical parameters of reproductive organs of an interesting class of biologically potent complexes on male albino rats at the dosages have been examined and discussed. Lead(IV) complexes have been synthesized using amino acids and 1,10-phenanthroline, 4,7-phenanthroline or 1,7-phenanthroline. A series of di-and tri-organolead(IV) [LPbR n L ] and [LPbClR n L ] complexes where, L = amino acid (tyrosine and phenylalanine) and L = 1, 10-phenanthroline, 4,7-phenanthroline or 1,7-phenanthroline and n = 2 or 3 have been prepared by the conventional methods. Structure elucidation has been done by IR, UV, 1 H, 13 C and 207 Pb NMR spectroscopy. On the basis of spectral evidences, it has been concluded that the carboxylic acid of the amino acid is behaving as a monodentate ligand in all these complexes and the complexes are octahedral in shape with a coordination number six around the lead atom. The complexes have been screened against a number of fungi and bacteria to assess their growth inhibiting potential. Lead complexes incorporating the chelating 1,10-phenanthroline ligand showed a range of activities. The metal free non-chelating ligands 1,7-phenanthroline and 4,7-phenanthroline were inactive and the complexes derived from 1,7-phenanthroline displayed only marginal activity.

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