Kalugin, V. E. published the artcileSynthesis of derivatives of pyrido[3′,2′:4,5]furo[3,2-c]isoquinoline heterocyclic system, Computed Properties of 612-13-5, the publication is Russian Chemical Bulletin (2014), 63(2), 426-430, database is CAplus.
An approach to the synthesis of derivatives of new heterocyclic system, pyrido[3′,2′:4,5]-furo[3,2-c]isoquinoline I [R = R1= Me; R = Ph, R1 = 4-MeC6H4, 2-thienyl; R = CF3, R1 = Ph], was suggested. A condensation reaction of substituted 3-cyanopyridin-2(1H)-ones with Me 2-(chloromethyl)benzoate and subsequent treatment of the condensation product with potassium tert-butoxide leads to substituted pyrido[3′,2′:4,5]furo[3,2-c]-isoquinolin-5(6H)-ones. Similarly, a condensation reaction of substituted 3-cyanopyridin-2(1H)-ones with 2-(chloromethyl)benzonitrile and subsequent treatment of the condensation product with potassium tert-butoxide gives substituted 5-aminopyrido[3′,2′:4,5]furo[3,2-c]-isoquinolines II.
Russian Chemical Bulletin published new progress about 612-13-5. 612-13-5 belongs to nitriles-buliding-blocks, auxiliary class Organic Pigment, name is 2-(Chloromethyl)benzonitrile, and the molecular formula is C8H6ClN, Computed Properties of 612-13-5.
Referemce:
https://en.wikipedia.org/wiki/Nitrile,
Nitriles – Chemistry LibreTexts