No / The structure of C16H10N4O4[HCl,1.5CH3OH],
Mr = 406.80, has been determined from X-ray diffraction
data. The crystals are monoclinic, space group C2/c, with
eight molecules per unit cell and a = 21.482(4),
b = 7.131(1), c = 24.495(5) A ° , b = 111.01(3) , crystal
density Dc = 1.546 g/cm3. The material was difficult to
crystallize and crystals produced were found to be poor
diffractors. Intensity data were measured at liquid nitrogen
temperature using a weakly diffracting crystal typical of
the batch. However the X-ray analysis has finally enabled
the chemical constitution of this cryptolepine derivative,
which was previously incorrectly assigned, to be
unequivocally established. Direct methods were used to
solve the structure which was refined by full-matrix least
squares to a conventional R-index of 0.0798 for 2,861
reflections and 268 parameters. The 7,9-dinitrocryptolepine
molecule is highly planar with a strong intramolecular
hydrogen bond between N(10) in ring C and O(92) of a
nitro group. There are a number of intermolecular hydrogen
bonds involving the cryptolepine derivative the
hydrochloride and both solvated methanols. One of the
methanol solvate molecules (methanol 2) is unusually
disordered with its C atom lying exactly on a crystallographic
twofold axis. Consequently the methanol OH and
H3 groups are at 0.5 occupancy and repeated by the twofold
symmetry.
| Identifer | oai:union.ndltd.org:BRADFORD/oai:bradscholars.brad.ac.uk:10454/4530 |
| Date | January 2008 |
| Creators | Lisgarten, J.N., Potter, B.S., Pitts, J.E., Palmer, R.A., Wright, Colin W. |
| Source Sets | Bradford Scholars |
| Language | English |
| Detected Language | English |
| Type | Article, No full-text in the repository |
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