Igor Simonič,a* Silvo Zupančič,a Amalija Golobič,b Ljubo Goličb and Branko Stanovnikb
a KRKA, d. d., Šmarješka cesta 6, SI-8501 Novo mesto, Slovenia
b Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana, Slovenia
* Corresponding author: E-mail: firstname.lastname@example.org
Diethyl (E)-4-[2-[2-(tert-butoxycarbonyl)vinyl]phenyl]-2,6-dimethyl-1,4-dihydropyridine-3,5-dicarboxylate or lacidipine (1) is a drug used for treatment of hypertension. The literature data for the undesired daylight phototransformation of compound 1 was confirmed for UV light as well. The main product, (1α,1aα,4aα,8bα,8cα) 1-(1,1-dimethylethyl) 4,8c-diethyl 1a,2,4a,8b-tetrahydro-1a,3-dimethyl-2-azacyclobuta[jk]fluorene-1,4,8c(1H)-tricarboxylate was isolated and the crystal structure was determined.
Keywords: 1,4-dihydropyridines, lacidipine, phototransformation, crystal structure