The chemistry of pyridine and its partially or completely hydrogenated analogues, used in various fields, is one of the fastest growing fields of interest for chemists and pharmacologists. Pyridine, pyridine, and tetrahydroisoquinoline rings are the major fragments of many natural and synthetic biologically active substances. Quaternary pyridinium salts are widely used as alkylating agents, interfacial migration catalysts, antiseptics, ionic liquids as surfactants and anticorrosives.

1. , MillsK.//Vkn .: Chemistry of heterocyclic associations.M .: Mir.-2004.-SL99.
2. Kuznetsov E. V., Pruchkin D. V., Dorofeenko G. N.// XGS-1974.-№ 2.- P. 181.
3. Bringmann G., Gulder Т., Reichert M., Meyer F. Ancisheynine, the First N, Coupled Naphthylisoquinoline Alkaloid: Total Synthesis and Stereochemical Analysis.//Org.Lett.-2006.-V.8.-N°6.-P.1037-1040.
4. Tolkunov V.S., Shishkin O.V., Zubatyuk R.I., Perepichka I.F., Dulenko V.I. Unusual Double 'O/N to N/O' Recyclization of 5-Alkyl-7,8-dimethoxy-2- aiylbenzo[d]pyrrolo[3,2-b]pyrylium Perchlorates into 5-Alkyl-7,8-dimethoxy-2- arylfuro[253-c]isoquinolines.//Synlett.-2005.-N°6.-P.1036-1038.
5. Achenbach, H., Hemrich, H., 1991. Constituents of tropical medicinal plants. Part 40.Alkaloids, flavonoids and phenylpropanoids of the West African plant Oxymitra velutina. Phytochemistry 30, 1265–1267.
6. Al-Wakeel, S.A.M., Moubasher, M.H., Roberts, M.F., 1995. Alkaloids fromGlaucium corniculatum(L.) of gyptian origin. Biochem. Syst. Ecol. 23, 337–338

Isoquinoline and many of its derivatives have different biological activities

DjoulDj., MillsK.//Vkn .: Chemistry of heterocyclic associations.M .: Mir.-2004.-SL99.

Kuznetsov E. V., Pruchkin D. V., Dorofeenko G. N.// XGS-1974.-№ 2.- P. 181.

Bringmann G., Gulder Т., Reichert M., Meyer F. Ancisheynine, the First N, Coupled Naphthylisoquinoline Alkaloid: Total Synthesis and Stereochemical Analysis.//Org.Lett.-2006.-V.8.-N°6.-P.1037-1040.

Tolkunov V.S., Shishkin O.V., Zubatyuk R.I., Perepichka I.F., Dulenko V.I. Unusual Double 'O/N to N/O' Recyclization of 5-Alkyl-7,8-dimethoxy-2- aiylbenzo[d]pyrrolo[3,2-b]pyrylium Perchlorates into 5-Alkyl-7,8-dimethoxy-2- arylfuro[253-c]isoquinolines.//Synlett.-2005.-N°6.-P.1036-1038.

Achenbach, H., Hemrich, H., 1991. Constituents of tropical medicinal plants. Part 40.Alkaloids, flavonoids and phenylpropanoids of the West African plant Oxymitra velutina. Phytochemistry 30, 1265–1267.

Al-Wakeel, S.A.M., Moubasher, M.H., Roberts, M.F., 1995. Alkaloids fromGlaucium corniculatum(L.) of gyptian origin. Biochem. Syst. Ecol. 23, 337–338