FAULMANN, CASSOUX, KOTOV AND YAGUBSKII 151 References Enraf-Nonius (1992). CAD-4 Express. Version 5.1. Enraf-Nonius, Delft, The Netherlands. Fair, C. K. (1990). MolEN. An Interactive Intelligent System for Crystal Structure Analysis. Enraf-Nonius, Delft, The Netherlands. Kotov, A. I., Fauimann, C., Cassoux, P. & Yagubskii, E. B. (1994). J. Org. Chem. 59, 2626-2629. Johnson, C. K. (1976). ORTEPII. Report ORNL-5138. Oak Ridge National Laboratory, Tennessee, USA. Neiland, O. Y., Kacens, Y. Y. & Kreicberga, Y. N. (1989a). Zh. Org. Khim. 25, 658~561. Neiland, O. Y., Kacens, Y. Y. & Kreicberga, Y. N. (1989b). Chem. Abstr. 111, 194689 K. North, A. C. T., Phillips, D. C. & Mathews, F. S. (1968). Acta Cryst. A24, 351-359. Sheldrick, G. M. (1985). SHELXS86. Program for the Solution of Crystal Structures. Univ. of G6ttingen, Germany. Wallis, J. D. & Dunitz, J. D. (1988). Acta Cryst. C44, 1037-1039. Williams, J. M., Schultz, A. J., Geiser, U., Carlson, K. D., Kini, A. M., Wang, H. H., Kwok, W.-K., Whangbo, M.-H. & Schirber, J. E. (1991). Science, 252, 1501-1508. thiophene ring is planar while the diazepine moiety adopts a half-chair conformation; the cis-fused piperi- dine ring possesses a chair conformation. The least- squares plane of the thiophene and the diazepine rings makes an angle of about 102 ° with the best plane of the piperidine moiety. Comment The reported anticonvulsant, anxiolytic, muscle-relaxant and central nervous system activity of fused tricyclic thienodiazepines (Bauer, Langbein & Weber, 1975; Weber, Bauer, Dannenberg & Kuhn, 1974; Hunkeler & Kyburz, 1981) stimulated the search in our laboratory for other heterocycles incorporating this ring system. The Beckmann rearrangement of 10-(hydroxyimino)- 6,7,8,9,9a, 10-hexahydro-4H-thieno[2,3-b]quinolizine (I) with polyphosphoric acid at 413 K led to the title com- pound (II) (Marchalfn & Decroix, 1994). Acta Cryst. (1995). C51, 151-152 4,6,7,8,9,9a-Hexahydro- 11H- pyrido- [ 1,2-a]thieno[ 2,3-e ][ 1,3 ]diazepin- 11 (10H)- one JOSEF KO~gEK,t LADISLAVULICK~'~:AND S~EFAN MARCHALtN§ Faculty of Chemical Technology, Radlinsk~ho 9, Slovak Technical University, CS-812 37 Bratislava, Slovakia Zomao ~s Polyphosphoric acid ~ N ~ o s 413K N~O H H (I) (II) The structure of (II) was inferred from exhaustive ~H and ~3C NMR studies. To confirm that the E configura- tion of the starting oxime (I) was retained and to obtain detailed stereochemistry of the new tricyclic heterocy- cle, the X-ray diffraction study of (II) was undertaken. The X-ray analysis shows that the molecule consists of a seven-membered diazepine ring fused to a five- membered thiophene ring and a six-membered piperi- dine ring. The thiophene ring is planar, while the Department of lnorganic Chemistry, Masaryk University, Kotlf~'sk6 2,611 37 Brno, Czech Republic BERNARD DECROIX Laboratoire de Chimie, Universitd de Havre, 30 rue Gabriel Pdri, 76600 Le Havre, France (Received l0 May 1993; accepted 8 February 1994) Abstract The title molecule (CllH14N2OS) consists of a seven- membered diazepine ring fused to a five-membered thio- phene ring and a six-membered piperidine ring. The t Departmentof Chemistry. Department of PhysicalChemistry. § Department of Organic Chemistry. HIO H4 H13 . ~ H9 H3 / NI~ C8~H11 H2 HS~ C 6 ~ I ~v~ I0 =" ~3 ~ H14- H8 ~H12 N2H6 Fig. 1. The molecular structure of the title compound, with displace- ment ellipsoidsgiven at 30% probability for non-H atoms. © 1995 International Union of Crystallography Printed in Great Britain - all rights reserved Acta Crystallographica Section C ISSN 0108-2701 ©1995