Structure of zizyberannalic acid

Sekar, K.; Parthasarathy, S.; Kundu, Amit; Barik, B. R.

doi:10.1107/s0108270192010047

Cited by 3 publications

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“…In both molecules there is an intramolecular O-HÁ Á ÁO hydrogen bond present forming an S(6) ring motif. Most piperidine derivatives are known to have chair conformations (Sekar & Parthasarathy et al, 1993). The title compounds are no exception and the piperidine rings (A = C10-C14/N1) adopt distorted chair conformations in both compounds.…”

Section: Structural Commentarymentioning

confidence: 99%

Crystal structures of two 2,9-dithia-13-azadispiro[4.1.4⁷.3⁵]tetradecan-6-ones

et al. 2015

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In the title compounds 4,11-dihydroxy-13-methyl-1,8-di-p-tolyl-2,9-dithia-13-azadispiro [4.1.4 7 . 3 5 ]tetradecan-6-one, C 26 H 31 NO 3 S 2 , (I), and 13-benzyl-4,11-dihydroxy-1,8-bis(4-methylphenyl)-2,9-dithia-13-azadispiro [4.1.4 7 .3 5 ]tetradecan-6-one, C 32 H 35 NO 3 S 2 , (II), the piperidine rings adopt distorted chair conformations. The thiophene rings in (I) have envelope conformations, with the spiro C atoms as the flaps. In (II), one thiophene ring (D) has an envelope conformation, with the hydroxy-substituted C atom as the flap, while the other thiophene ring (E) has a twisted conformation on the C-C bond involving the spiro C atom and the toluyl-substituted C atom. In (I), the mean plane of the piperidine ring makes dihedral angles of 75.16 (9) and 73.33 (8) with the mean planes of the thiophene rings (D and E), respectively. In (II), the corresponding dihedral angles are 70. 95 (11) and 77.43 (12) . In both compounds, there is an intramolecular O-HÁ Á ÁO hydrogen bond forming an S(6) ring motif. In the crystal of (I), molecules are linked via O-HÁ Á ÁN and C-HÁ Á ÁO hydrogen bonds, forming chains along [010]. There are also -interactions present involving inversion-related benzene rings, linking the chains to form slabs parallel to (100). In the crystal of (II), molecules are linked via O-HÁ Á ÁO hydrogen bonds, forming inversion dimers with an R 4 4 (8) ring motif. The dimers are linked by C-HÁ Á Á interactions, forming slabs parallel to (001). Chemical contextPiperidine derivatives have had an important impact in the medical field due to their wide variety of pharmacological activities, and they form an essential part of the molecular structure of important drugs (Hema et al., 2005a,b). Piperidine derivatives are used clinically to prevent post-operative vomiting, to speed up gastric emptying before anaesthesia or to facilitate radiological evaluation, and to correct a variety of disturbances of gastro-intestinal functions (Hema et al., 2005a,b). The piperidine structural motif is present in natural alkaloids (Raghuvarman et al., 2014). Notably it is found in the fire ant toxin solenopsin and is an inhibitor of phosphatidylinositol-3-kinase signalling and angiogenesis (Rajalakshmi et al., 2012). Piperidines are known to have CNS depressant action at low dosage levels and stimulant activity with increased doses. They have been used as antitumor (Nguyen Thi Thanh et al., 2014) ]tetradecan-6-one derivatives, each incorporating a piperidine ring, and report herein on their crystal structures. Structural commentaryThe molecular structure of compounds, (I) and (II), are shown in Figs. 1 and 2, respectively. A view of the structural overlay of the two compounds is shown in Fig. 3. The essential differences appear to be related to the orientations of the toluyl substituents, viz. rings B an C.In both molecules there is an intramolecular O-HÁ Á ÁO hydrogen bond present forming an S(6) ring motif. The molecular structure of compound (I), showing the atom labelling. Displacement ellipsoids ar...

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Section: Structural Commentarymentioning

confidence: 99%

Crystal structures of two 2,9-dithia-13-azadispiro[4.1.4⁷.3⁵]tetradecan-6-ones

et al. 2015

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“…Even though the unsubstituted N-nitrosopiperidines are potential carcinogens, when an alkyl group is substituted at the position C2, it reduces the carcinogenicity (Hema et al, 2005). Most of the piperidine precursors are known to exist in chair conformations (Sekar & Parthasarathy, 1993). The properties of the piperidine derivatives depend upon the nature of the side groups and their orientations.…”

Section: Commentmentioning

confidence: 99%