TY JOUR TI IR spectra and structure of chromenopyridine carbonitrile systems KW 5-amino-2,4-diimino-3-(pyridine-2-yl)-2,3,4,10b-tetrahydro-1H-chromeno[3,4-c]pyridine-1-carbonitrile KW 4-amino-2,5-diimino-3-(pyridine-2-yl)-2,3,5,10b-tetrahydro-1-chromeno[3,4-c]pyridine-1-carbonitrile KW chromedopyridine carbonitrile systems KW geometrical structure KW IR spectrum JO Russian Journal of Biological Physics and Chemisrty AU Ivlieva (Peretokina), I.V. AU Mecheryakova, A.A. AU Babkov, L.M. AU Sorokin, V.V. PY 2021 IS 6 PB Federal State Educational Institution of Higher Education Sevastopol State University