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A stereoselective strategy for the replacement of the 1,2-dihaloalkene bridge of tetrahalonorbornyl derivatives by an oxygen bridge involving stepwise controlled oxidation, cleavage of the dione thus formed, and reiterative intramolecular S(sub N)2 displacement of two bridgehead halogens is devised. The synthesis of four highly strained pentacyclic bis-oxa-bridged derivatives with interesting structural variations is presented.

Research has been conducted on the gamma-lactone-fused cyclopentanoids. The effect of the tetrahalonorborene derivatives' structural flexibility and stereochemical control on these cyclopentannulated gamma-lactones has been investigated and the details are described.

A simple computational model explains and predicts pi-facial selectivity in nucleophilic additions to sterically-free carbonyls. The model, based on MNDO, uses two sets of calculations. One measures electrostatic and polarization effects using a test charge to represent the nucleophile, while the other models the hydride ion to determine the added role of orbital interactions. Using these two, the approach is able to reproduce most empirically-established selectivities, especially with the hydride model.

Stereoselective formal synthesis of (_)-neplanocin A from a cyclopentane derivative is described by using an elegant strategy involving reiterative usage of an already existing acetonide protecting group. The acetonide protecting groups that is carried forward intact right from the starting adduct to an advanced intermediate is shuffled around twice as in a relay race through the synthetic sequence, which has avoided unnecessary employment of additional protecting groups.

A study aimed to achieve a short and stereoselective route to the trans-hydrindane derivative, which is a potential building block for the synthesis of steroidal and related molecules. The desired results were obtained by the operation of indium, tin, and ruthenium based reagents, starting from a tetrabromo norbornyl derivative.

Research has been conducted on 7-azaspiro[4.5]decan-6-ones. The authors describe the access to these compounds which involves regio- and chemoselective reactions and starts from tetrabromonorbornyl derivatives.