Oligoglyceric acid synthesis by autocondensation of glyceroyl thioester

The autocondensation of the glyceroyl thioester S-glyceroyl-ethanethiol yielded oligoglyceric acid. The rates of autocondensation and hydrolysis of the thioester increased from pH 6.5 to pH 7.5 in 2,6-lutidine and imidazole buffers. Autocondensation and hydrolysis were much more rapid to imidazole buffers than in 2,6-lutidine buffers of the same pH. The efficiency of ester bond synthesis was about 20% for 40 mM S-glyceroyl-ethanethiol in 2,6-lutidine and imidazole buffers near neutral pH. The size and yield of the oligoglyceric acid products increased when the concentration of the thioester was increased. The relationship of these results to prebiotic polymer synthesis is discussed.