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Oligo 5′-thiodeoxythymidylates and oligo 5′-thiodeoxyadenylates were prepared via displacement of tosylates by thiophosphate mono- and diesters. The 5′ ends contain O-tosyl or S-phosphoryl groups, while the 3′ ends terminate in deoxythymidine. The types of starting materials used for such polymerization were 5′-O-tosyl nucleoside 3′ cyanoethyl phosphorothionates and the corresponding monoesters. Both oligonucleotide analogs possess secondary structure according to spectral evidence.

Summary We are proposing a simple model by which acidic polysaccharides of the critical charge density 1 minus/1 carbohydrate unit can be converted into anion exchangers by complexing with a trivalent cation. We have constructed a complex of alginic acid and Al3+ which was shown to bind nucleotides. It was assumed that bile acids would also be bound and, thus, Al- alginate would be hypocholesterolemic in vivo . The feeding of Al- alginate to rats which were fed a high cholesterol diet produced a marked decrease of serum cholesterol. It is proposed that Al3+ may have a nutritional role if present in conjunction with acidic polysaccharides. Ternary complexes involving lipids may exist in many biological structures.

The biochemical properties of several alkyl phosphotriesters of cyclic AMP were studied with respect to their interactions with beef heart protein kinase and cyclic nucleotide phosphodiesterase. Ethyl and propyl triesters did not enhance the phosphorylation of histone by protein kinase and methyl, ethyl, propyl and butyl triesters were poor competitors for the cyclic AMP binding site of the enzyme. However, these alkyl phosphotriesters were effective inhibitors of cyclic nucleotide phosphodiesterase with the K i 's arrayed in the following order: methyl > ethyl > propyl > butyl > cetyl triester. Metabolic studies with mice indicated that intraperitoneal injection of low doses of propyl triester for one week significantly increased cyclic AMP concentration.