The use of the silylation reaction in the synthesis of peptides from L-lysine

Summary 1. A number of peptides have been obtained from L-lysine by the application of the silylation method.2. The peptides obtained can be used as intermediates in the synthesis of biologically active substances.All-Union Institute of the Technology of Blood Substitutes and Hormone Preparations, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 4, pp. 482–485, July–August, 1978.     

Conversion of polyalkylated cyclohexadienones to alkylphenols with bases

Conclusions The dealkylation of polyalkylcyclohexadienones forming polyalkylphenols is accomplished by the action of strong bases at 250–320°C.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 4, pp. 936–937, April, 1976.     

Synthesis,composition, and properties of products formed in interaction of <Emphasis Type="Italic">ortho-tert</Emphasis>-butylphenol with sulfur monochloride

Interaction of ortho-tert-butylphenol with sulfur monochloride in dimethylformamide leads to an increase in the fraction of phenol di- and polysulfides in the product. Liquid chromato-mass-spectrometry was used to determine the composition of the main groups of compounds contained in the mixture. A number of its components was isolated and produced by counter synthesis.     

Synthesis of a heptapeptide with sequence 17–23 of human calcitonin

Two schemes for the synthesis of a peptide with sequence 17–23 of human calcitonin with the minimum protection of the lateral functions of the amino acids are proposed.     

About selective methods of synthesis of 6-<Emphasis Type="Italic">tert</Emphasis>-butyl-2-methylphenol and 6-<Emphasis Type="Italic">tert</Emphasis>-butyl-2,4-dimethylphenol

Vapor phase catalytic methylation with methanol of 2-tert-butylphenol at the temperature 280–300°C proceeds selectively with formation of 6-tert-butyl-2-methylphenol. Elevating reaction temperature above 300°C leads to formation of 2,6-dimethylphenol. Reaction of 2-tert-butylphenol with methanol in alkaline medium in the presence of zinc oxide is shown to lead initially to formation of a mixture of calixarenes and methylenebisphenols that at elevated temperature exert splitting leading in future to 6-tert-butyl-2,4-dimethylphenol. Obtaining it in this reaction from 2,2′-methylenebis-(6-tert-butyl-4-methylphenol) proceeds selectively. Pathways of the reductive methylation of methylenebisphenols with methanol in alkaline medium is considered.     

Preparation of hydrazides of amino acids and peptides

A new method of synthesizing hydrazides of amino acids and peptides is considered which involves the hydrazinolysis of the silyl esters of the corresponding compounds. A number of hydrazides of derivatives of amino acids and peptides has been obtained in high purity with yields close to quantitative. The physicochemical characteristics of the compounds synthesized are given.All-Union Scientific-Research Institute of the Technology of Blood Substitutes and Hormones Preparations, Moscow. Translated from Khimiya Prirodnykh Soedinenii, No. 5, pp. 684–686, September–October, 1979.