[Experimental basis for the tentative permissible levels of phthalazol, sulfadimethoxine and Bepask in bodies of water].

Tentative permissible levels (TPL) of phthalazol, sulfadimethoxine, and Bepask in the water were substantiated on the basis of study of organoleptic properties, of influence on sanitary status of water bodies and toxicologic characteristics of these substances. TPL of studied chemicals accordingly are (mg/dm3): 12, 1 and 6.8.

[Synthesis of poly (Lys-Ser-Glu) and study of its antigenic and immunogenic properties].

We have synthesized oligo- and polypeptides containing lysin, serine and glutamic acid residues. Di- and tripeptides were prepared by the successive elongation of C-terminus by means of the N,N'-dicyclohexylcarbodiimide or mixed anhydride methods. The oligopeptides were obtained by block condensation of pentafluorophenyl esters of tripeptides, and polypeptides by polycondensation of dipeptide 2,4,5-trichlorophenyl esters.