Jownal of Chromatography, 91 (1974) 113-l 18 0 Elsevier Scientific Publishing Company, Amsterdam - Printed in The Netherlands CHROM. 7146 GAS CHROMATOGRAPHIC STUDIES OF DERIVATIVES OF CELLULINE- LIKE SUBSTANCES EVA TOMORI Research institute for Pharmaceutical Chemistry, Budapest (Hungary) and H. KALASZ, J. NAGY and J. KNOLL Scmmclweis Medical University Department of Pharmacology. Wldapcst (Hungary) SUMMARY Different aspects of the gas chromatographic determination of the celluline-like substances exhibiting’specific cardiotonic activity are discussed. zyxwvutsrqponmlkjihgfedcba As this substance is isolated from frog skin and bladder, many impurities have to be considered. Determination of these samples, having a broad range of boiling points, was perform- ed by means of programmed-temperature gas chromatography. Identification of unknown peaks was executed with the help of pure standard substances and retention indices. INTRODUCTION Celluline, detected in 1952 by Knoll zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONM et al.', is an endogenous substance exerting a specific mode of action and plays a particular role in myocardial cell membrane transformations from the systolic to the diastolic phase. In the course of several years of research a number of celluline-like components were detected and isolated from different tissue perfusates (frog skin, frog bladder, frog liver, etc.). Biological activity can be demonstrated on isolated frog heart brought diastolically to hypodynamia by means of celluline-specific Ringer solution. This hypodynamia could not be reversed by known cardiotonic agents. Celluline, however, spontaneously caused immediate contractions in the isolated frog heart even in celluline-specific Ringer solution con- taining mainly potassium ions. Raw materials isolated from frog skin and bladder as well as freeze-dried raw powders were purified and fractionated by means of gel chromatography, thin-layer chromatography, ion-exchange chromatography, and electrophoresis. The individual fractions were pooled according to their UV absorption spectra and their biological activity. The UV and IR spectra, as well as the gas chromatographic and mass spec- trometric characteristics, of the purified products were studied. According to direct and indirect proofs 2*3 the principle responsible for biological activity is a calcium complex containing a variety of organic ligands. Structure determination studies