organic papers Acta Cryst. (2006). E62, o4527–o4528 doi:10.1107/S160053680603724X Ali et al.  C 17 H 15 N 3 O 2 o4527 Acta Crystallographica Section E Structure Reports Online ISSN 1600-5368 2-Methyl-1H-indole-3-carbaldehyde 4-hydroxy- benzoylhydrazone Hapipah M. Ali, a Mohd Idris Najwa, a Ming-Jin Xie b and Seik Weng Ng a * a Department of Chemistry, University of Malaya, 50603 Kuala Lumpur, Malaysia, and b School Chemistry, Yunnan University, Kunming 650092, People’s Republic of China Correspondence e-mail: seikweng@um.edu.my Key indicators Single-crystal X-ray study T = 295 K Mean (C–C) = 0.002 A ˚ R factor = 0.043 wR factor = 0.124 Data-to-parameter ratio = 15.3 For details of how these key indicators were automatically derived from the article, see http://journals.iucr.org/e. Received 12 September 2006 Accepted 13 September 2006 # 2006 International Union of Crystallography All rights reserved The NH group of the methylindolecarbaldehyde moiety and the OH group of the hydroxybenzoylhydrazone moiety of the title compound, C 17 H 15 N 3 O 2 , interact to form a linear chain; adjacent chains are linked through the amide –N(H)— C( O)– portion of the molecule to form a tightly held three-dimensional network structure. Comment This study continues our work on Schiff bases that are formed by condensing 2-methylindole-3-carbaldehyde with an aroyl- hydrazine (Ali et al., 2006). In the title molecule, (I) (Fig. 1), the amine group of the methylindole-3-carbaldehyde moiety interacts with the hydroxy group of the hydroxybenzoyl- hydrazine moiety of a neighboring molecule to form a linear chain. In the –N(H)–C( O)– portion, the –NH unit serves as a hydrogen-bond donor and the C O unit as a hydrogen- bond acceptor (Table 1), these hydrogen-bonding interactions consolidating the three-dimensional network into a tightly held architecture. Experimental 2-Methylindole-3-carbaldehyde (0.44, 2.7 mmol) and 4-hydroxy- benzhydrazide (0.42 g, 2.7 mmol) were heated in ethanol (100 ml) for 2 h. The solvent was removed and the pure compound obtained by recrystallization from dimethylformamide. Crystal data C 17 H 15 N 3 O 2 M r = 293.32 Monoclinic, P2 1 =c a = 12.171 (1) A ˚ b = 14.090 (1) A ˚ c = 8.6767 (7) A ˚  = 97.917 (1)  V = 1473.8 (2) A ˚ 3 Z =4 D x = 1.322 Mg m 3 Mo K radiation  = 0.09 mm 1 T = 295 (2) K Block, yellow 0.31  0.27  0.24 mm Data collection Bruker APEX-II area-detector diffractometer ’ and ! scans Absorption correction: none 13436 measured reflections 3236 independent reflections 2516 reflections with I >2(I) R int = 0.024  max = 27.1 