the ability of the present semiempirical quantum mechanics methods are surveyed for reproducing the transannular interaction in the bifunctional n-phenyl-5-azocanones. the am1 method is the best with the order of reliability being am1, pm3, mndo and mindo/3. am1 calculations were then carried out for quantification of transannular interaction. the n(o) ionization potential has been used for thi...

Xhaffer (1)) Myers and Fine (2), and Hahn and Meyer (3) adduced evidence that muscle creatine is the precursor of urinary creatinine. This was questioned by Chanutin and Kinard (4) but was conclusively proved by Bloch, Schoenheimer, and Rittenberg (5, 6) by isotope tracer evidence, which also showed that creatinine was the only normal urinary constituent containing any significant amount of bod...

Recognition of the significant role played by the sulphydryl group places a powerful tool in the hands of experimenters in cell proliferation, be they biologists, physiologists, pathologists, or others interested in this field. There are two fundamentals which must be appreciated, viz., first, -SH is the naturally occurring chemical group in cell division, as actually discovered in dividing cel...

Motivated by the need for chemical strategies designed to tune peptide fragmentation to selective cleavage reactions, benzyl ring substituent influence on the relative formation of carbocation elimination (CCE) products from peptides with benzylamine-derivatized lysyl residues has been examined using collision-induced dissociation (CID) tandem mass spectrometry. Unsubstituted benzylamine-deriva...

An enantioselective sulfimidation of 3-thiosubstituted 2-quinolones and 2-pyridones was achieved with a stoichiometric nitrene source (PhI=NNs) silver-based catalyst system. Key to the success reaction is use chiral phenanthroline ligand hydrogen bonding site. The enantioselectivity does not depend on size two substituents at sulfur atom but only binding properties heterocyclic lactams. A total...

Boyland, E., Manson, D. & Sims, P. (1953). J. chem. Soc. p. 3623. Boyland, E., Manson, D., Sims, P. & Williams, D. C. (1956). Biochem. J. 62, 68. Bray, H. G. & Thorpe, W. V. (1954). In Method8 in Biochemical Analysi8, vol. 1, p. 45. Ed. by Glick, D. New York: Interscience. Burkhardt, G. N., Ford, K. W. G. & Singleton, E. (1936). J. chem. Soc. p. 17. Burkhardt, G. N. & Lapworth, A. (1926). J. ch...