1. Spiro-[cyclo-pentane-1,2'(1'H)-pyrido[2,3-d]pyrimidin]-4'(3'H)-one
Daxin Shi, Liupan Yang, Jianhong Tang, Xiuzhen Wang, Jiarong Li Acta Crystallogr Sect E Struct Rep Online. 2010 Aug 18;66(Pt 9):o2301. doi: 10.1107/S1600536810027479.
The title compound, C(11)H(13)N(2)O, was obtained by cyclo-condensation of 2-amino-pyridine-3-carbonitrile with cyclo-penta-none. The mol-ecule is built up from two fused six-membered rings and one five-membered ring linked through a spiro C atom. Both the pyrimidine and the cyclo-pentane rings adopt envelope conformations. In the crystal structure, mol-ecules are linked by inter-molecular N-H⋯O hydrogen bonds.
2. Rupatadine
Manpreet Kaur, Jerry P Jasinski, Zane A Luopa, Neeraj Kumar, Nilesh G Patel, Omprakash Gudaparthi, H S Yathirajan Acta Crystallogr Sect E Struct Rep Online. 2013 May 31;69(Pt 6):o980. doi: 10.1107/S1600536813014256. Print 2013 Jun 1.
8-chloro-11-{1-[(5-methyl-pyridin-3-yl)meth-yl]piperidin-4-yl-idene}-6,11-di-hydro-5H-benzo[5,6]cyclo-hepta-[1,2-b]pyridine), C26H26ClN3, the dihedral angle between the mean planes of the chloro-phenyl and cyclo-hepta-[1,2-b]pyridinyl rings fused to the cyclo-heptane ring is 56.6 (1)°. The mean planes of the cyclo-hepta-[1,2-b]pyridinyl and 5-methyl-pyridin-3-yl rings are twisted by 64.9 (4)°. The central piperizene group is in a slightly distorted chair configuration. A weak intra-molecular C-H⋯N inter-action is observed between the cyclo-hepta-[1,2-b]pyridinyl and piperidin-4-yl-idene moieties.
