Redirected from Heterocyclic
That is, unlike the carbon-only ring like in benzene and napthalene, there are other elements in the backbone, such as in pyrimidine and purine.
... Upravleniye[?] (OGPU, 1923-1934) Narodnyi Kommissariat Gosudarstvennoi Bezopastnosti[?] (NKVD, 1934-1943) Ministerstvo Gosudarstvennoi Bezopastnosti[?] (MGB, ...