sugars as building blocks for replicating systems, these results direct thinking once again toward ribose itself, and chemical work seeking an improved abiotic synthesis of ribose would be most desirable.(16) Note Added in Proof: In the synthesis of these oligomers, coupling yields were ca. 90% for glycerothymine and >99% for natural nucleosides. The product oligonucleotides were purified by reversed phase HPLC (Nucleosil C-4 column, gradient from 15% to 30% acetonitrile in 0.1 M triethylammonium acetate) prior to the removal of the 5'-trityl groups and detritylated (80% acetic acid). Samples of the oligonucleotides containing the flexible base were digested with spleen phosphodiesterase, snake venom phosphodiesterase, and bacterial alkaline phosphatase. HPLC of the digests showed the expected nucleosides in their expected ratios.

Palladium-catalysed reaction of disilanylstannanes with alkynes afforded ((3-disilanylalkenyl)stannanes, which underwent subsequent reaction w i t h phenylethyne in the presence of palladium catalyst giving the corresponding 1 -si la-4-sta n nacyclo hexa-2,5-d ienes.