Letters in Organic Chemistry - Volume 1, Issue 2, 2004

An improved method for the synthesis of trimethylsilylethyl chloroformate (Teoc-Cl) was studied in great detail. N-Teoc-adenosine, N-Teoccytidine and their deoxyribonucleoside derivatives were synthesized as the key synthetic intermediates for the synthesis of base-sensitive oligonucleotide derivatives by use of N-methylimidazole. The stability and chemical properties of these Nprotected nucleoside derivatives were examined.

The applicability of 2,2-bis(ethoxycarbonyl)-3-(pivaloyloxy)propyl and 2- cyano-2-(2-phenylethylaminocarbonyl)-3-(pivaloyloxy)propyl groups as biodegradable protecting agents for the internucleosidic linkages of phosphorothioate antisense oligonucleotides has been studied. For this purpose, protected phosphoromonothioates of thymidylyl-(3'→5')-thymidine [Tp(s)T] containing either a bridged or non-bridged sulfur at Read More

Four unprecedented vibsane-type diterpenes, named cyclovibsanin A, 15-Omethylcyclovibsanin A, 15-O-methylcyclovibsanin B, and 3-hydroxy-15-O-methylcyclovibsanin A, were isolated from the leaves of Viburnum awabuki. Their unique tricyclo[6.3.2.00,0]tridecane structures and plausible biosynthesis of cyclovibsanins are discussed here.

Four cell membrane-permeant derivatives of polyaza macrocyclic ligands, including acetoxymethyl (AM) and pivaloyloxymethyl (POM) esters of 1,4,7,10-tetraazacyclododecane- 1,4,7,10-tetrakis(ethyl methylenephosphonate) (DOTPME) and 1,4,7-triazacyclononane- 1,4,7-tris(ethyl methylenephosphonate) (NOTPME), were prepared as model systems for the detection of intracellular ions by 31P NMR spectroscopy. Pr Read More