Kamlesh J. Padiya

NBS-DMSO as a Nonaqueous Nonbasic Oxidation Reagent for the Synthesis of Oligonucleotides

A new method for the oxidation of nucleoside phosphite triester into phosphate triester under nonbasic and nonaqueous conditions using NBS-DMSO in CH(3)CN has been developed. The utility of this method for solution- and solid-phase synthesis of oligonucleotide is demonstrated.

Large scale, liquid phase oligonucleotide synthesis by alkyl H-phosphonate approach.

A new approach to the liquid phase synthesis of oligonucleotide is described, it is based on oxidative coupling using alkyl H-phosphonate synthon and polyethylene glycol (PEG5000) as a soluble support. Nucleoside alkyl H-phosphonate undergoes oxidative coupling in presence of NBS. The use of polyethylene glycol as a soluble polymeric support preserves some convenient features of the solid phase synthesis with new interesting advantages. This liquid phase method appears effective in terms of speed and coupling yield and can be evaluated for the production of large amount of oligonucleotide (100 microM).

An efficient oxidizing reagent for the synthesis of mixed backbone oligonucleotides via the h-Phosphonate approach

The mixture of carbon tetrachloride, N-methyl morpholine (NMM), pyridine and water in acetonitrile has been exploited for the oxidation of dinucleoside H-phosphonate diesters to the corresponding phosphates. The system is found to be inert to the phosphoramidate (P-N) and the phosphorothioate (P-S) linkages and has successfully been applied to the solid phase synthesis of mixed-backbone oligonucleotides (MBOs).

Halogenation of Aromatic Compounds by using Sodium Perborate as an Oxidant

A facile method for the halogenation of benzene and its derivatives by aqueous haloacids (HCl and HBr) using sodium perborate as an oxidising agent in the presence of tertabutylammonium bromide as a phase transfer catalyst is described.

Friedel–Crafts Acylation Reaction using Polymer Supported Aluminium Chloride

Friedel–Crafts reactions using polymer supported AlCl3 are reported and the effect of crosslinking level on ortho:para ratio is studied.

Solid phase oligonucleotide synthesis by using β-CE H-phosphonate approach

ABSTRACT A new approach to the solid phase synthesis of oligonucleotide is described, which is based on oxidative coupling of nucleoside 3′-β-CE H-phosphonates in presence of N-Bromosuccinimide (NBS) as a coupling agent.

Debromination of α-Bromo Ketones using Polymer-supported Triphenylphosphine†

An effective method for the debromination of α-bromo ketones using polymer-supported triphenylphosphine is described.

A NEW AND SELECTIVE OXIDISING REAGENT FOR OLIGONUCLEOTIDE SYNTHESIS

A mixture of carbon tetrachloride, N-methylmorpholine and water in acetonitrile serves as an excellent reagent for oxidation of nucleoside phosphite to nucleoside phosphates and has been successfully applied to the solid phase synthesis of d(CGTAAAATGG).