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Research has been conducted on the carbafuranosylamines. The chiral synthesis of these compounds has been carried out and the results indicate that they can be used as secondary structure-inducing platforms for engineering the biomimetic structures and glycopeptidomimetics.

Research has been conducted on the carbasugars. The siloxy diene-based construction of these carbasugars has been investigated via the silylative cycloaldolization protocol and the results are reported.

Research describes a methodology for an enantiospecific syntheses of pseudo-sugars and their variants. Construction of novel nonracemic pseudo-pyranoses, pseudo-furanoses of the D sugar type starting from D-glyceraldehyde acetonide and the corresponding ring-based dienoxy silane pair is presented.

Results point out that the utility and malleability of the vinylogous version of the Mukaiyama aldol and Mannich-type addition reactions with heterocyclic triad building modules for the synthesis of a repertoire of annonaceous acetogenin core units and their nitrogen and sulfur analogues.

A diversity-oriented protocol is developed for the assembly of densely hydroxylated cycloheptane amino acids via succession of a vinylogous Mukaiyama aldol reaction (VMAR), a Morita-Baylis-Hillman reaction (MBHR), and an intramolecular pinacol coupling reaction (IPCR). The parallel, asymmetric syntheses of four cycloheptane representatives proceed with high diastereocontrol and virtually complete enantioselectivity in ten steps and overall yields of 15-37%.

Stereoselective synthetic route to L-glutamic acid related to amino acid provide a foundation for the synthesis of novel metabotropic glutamate receptor probes and relevant densely functionalized carba-ketose constructs.

The experiment conducted to achieve the efficient, total synthesis of novel 2-deoxy-2-amino-5a-carba-beta-L-mannopyranuronic acid and 2-deoxy-2amino-5a-carba-beta-L-mannapyranose, is presented. The method used in this study is based on a rational adaptation of original project and involves the use of a suitable chiral nonracemic aldimine predecessor.

Research has been conducted on vinylogous aldol and silylative aldol addition reactions. The authors describe the feasibility of these reactions which involve pyrrole- and furan-based dienoxysilanes in the synthesis of carbasugar framework.

Efficient, total syntheses of novel 2-deoxy-2-amino-5a-carba-β-L-mannopyranuronic acid (1) and 2-deoxy-2-amino-5a-carba-β-L-mannopyranose (2), a positional stereoisomer of validamine, have been achieved in 28% and 24% overall yields and in 12 steps and 13 steps, respectively, from 2-[(tertbutyldimethylsilyl)oxy]furan (3) and (2S)-2,3-O-isopropylideneglyceraldehyde N-benzyl imine (4) via two highly diastereoselective Mukaiyama aldol-related chemical maneuvers. The strategy, which furnishes the targeted carbasugars in enantiopure forms, allows for complete control of the configuration at all five contiguous stereocenters of the targets by utilizing the sole element of chirality present in the aldimine progenitor 4. [ABSTRACT FROM AUTHOR]

The feasibility of sequential vinylogous aldol (intermolecular)/silylative aldol (intramolecular) addition reactions involving furano and pyrrole-based dienoxysilanes, 6 and 12, in the synthesis of carbasugar frameworks is illustrated by the preparation of the scantily investigated carbaseptanose and carbaoctanose representatives of this class of compounds. The target compounds, 1, 2, 3, ent2, ent-3, and 4, were obtained from readily available carbohydrate precursors (5 and 19) in yields of 21-30% over 8-12 steps. The irreversible silylative ring-closing aldolisation of γ-substituted dihydro-5H-furan-2-one and pyrrolidin-2-one aldehydes (9, 16, ent-16, and 22) driven by the TBSOTf/ Pr[sup i, sub 2]EtN Lewis acid-Lewis base couple was shown to be a practical, diastereoselective maneuver to forge the densely functionalized, medium-sized core carbocycles. [ABSTRACT FROM AUTHOR]

Investigates the chiral and divergent synthesis of carbafuranosyl amines. Hydrolytic breakage of the lactam; Identification of the pseudo-anomeric site of the cycloalkane moiety; Structure of the carbasugars.

Examines the silyloxy diene-based construction of carbasugars for the synthesis of four carbocyclic furanose and pyranose analogues. Introduction of novel silylative cycloaldolization protocol; Efficiency of synthetic sequence; Formation of carbafuranoses and thiols.