INVESTIGATION OF CYANO-METHYLATION REACTION BY CYANO-HYDRINE AND ITS DETERMINATION IN TOBACCO-SMOKE. ( STRECKER-REACTIONS )

Abstract

The results of our research work [1-7] of several years aimed at the binding of the unhealthy components of tobacco smoke directed our attention to the analysis and identification of the unknown peak observed during the high sensitivity radiochromatographic analysis of tobacco smoke condensates.It was a fruitless effort to remove the formaldehyde, the ac- etaldehyde and hydrogen cyanide present in tobacco smoke, or even to try to eliminate them separately, during the analysis the new, unknown peak appeared again and again on the radiochromatogram. During our research work we stated, that we were facing the Strecker reaction [8-9], known since 1850, that is, with the formation of cyanohydrine of the aldehydes and hydrogen cyanide present in tobacco smoke, corresponding to the new peak. Cyanohydrines to react quickly and energetically with basic aminoacids, during which reaction cyanomethyl derivatives are being formed. This reaction is proceeding also under physiological circumstances with the basic amino groups of proteins, contributing to the development of respiratory and cardiovascular insufficiencies. By means of model reactions and using solutions of tobacco smoke gases the process of the reaction was proved in a primary way, also its circumstances having been cleared. By radiochromatographic measurements it was proved that the labelled L-lysine-6 H is being cyanomethylated by formaldehyde-cyanohydrin at an extraordinary speed and cyanomethylation is complete within a very short time (5 min). The tests carried out on formaldehyde- C, cyanide- C and inactive L-lysine led to similar results, with a yield 93.9 percent within 5 min in all these cases. It was proved also by 13C NMR, 13C NMR DEPT and 1H NMR spectroscopic measurements that inactive L-lysine is cyanomethylated by cyanohydrine in an extraordi- narily energetic and quick reaction, according to the reaction mechanism supposed by us. Our results obtained during the radiochromatographic analysis of tobacco smoke conden- sate agreed in all respects with the model test results. That is, the cyanohydrine formation is proceeding very quickly in the tobacco smoke too (by the reaction of aldehydes with hydrogen cyanide contained by tobacco smoke) which can be unequivocally traced back to the Strecker-reaction recognized 140 years ago. The mechanism of the reaction was described by LAPWORTH in 1903. [10)]