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Synthesis of homogeneous hepta-antennated C-6 branched sialosyl cyclomaltoheptose derivatives were performed in good yields and the compounds were fully characterized. The preparation of such multivalent sialosidea with potential biorecognizable properties contributes to expand the existing array of such glycoforms.

The chemoenzymatic synthesis of the racemate and the one enantiomer of the fluorinated analogue of the natural cyclooxygenase inhibitor lasiodiplodin is described. The formation of the 12-membered lactone by a ring-closing metathesis is the key step in this synthesis.

A synthesis of the C(29)-C(45) bis-pyran subunit of spongistatin 1 is described. The C(29)-c(45) bis-pyran subunit can be assembled through an aldol reaction between a suitably functionalized F-ring methly ketone and 2,3-syn aldehyde.

P-nitrosophosphates represent new asymmetric N-O heterodienophiles that react with 1,3-dienes to produce complex oxygen-, nitrogen-, and phosphorous- containing cycloadducts and permit the direct introduction of the phosphoramidate functional group. P-nitrosophosphates also reacts with water to yield nitoxyl, the biologically important one-electron-reduced form of nitric oxide.

Reaction conditions are developed for the conjugate addition of alpha-nitrogen heteroatom functionalized cuprate reagents with the less reactive carboxylic acid derivatives. The conjugate addition reactions of alpha-aminoalkylcuprates to alpha,beta-unsaturated carboxylic acid derivatives proceeds eventually when used with CuCN.2LiCl.

The synthesis, characterization and dynamic nature of gem-dimethyl-functionalized cyclooctapyrrole and cyclododecapyrrole are presented. Formation of the larger cyclododecapyrrole is a result of the gem-dimethyl effect.

A study was conducted to analyze the tautomeric exchange of the inner hydrogens of free base alkylporphycenes using 13CCPMAS and 15N-CPMAS nuclear magnetic resonance (NMR) at different temperatures. The Bruker MSL-300 was utilized to determine the CPMAS NMR spectra. Results indicated the possibility of detecting rotations in the alkyn chains by determining variations in the relaxation times as a function of temperature.

A study was conducted to characterize the geometry, tautomerism, isomerism and stability of porphyrin isomers. Twenty seven structures based on E/Z-configurations and NH tautomerism were analyzed in the study. Computations were carried out using a Pople Gaussian 92 DFT program. Results indicated a rapid interconversion between two anti tautomers. Findings also suggested that the rate of exchange was sensitive to both temperature and isotopic substitutions.