and solution techniques. The single crystal structures of both co-
crystals have been analysed. The rare case of the simultaneous
existence of pure hydrogen bonded and partially ionic carboxylic
acid/nitrogen base dimers is observed within the same crystal
structure. These two types of O–H/Npyridine synthons result
from different intermolecular environments.
Pharmacological action of co-crystals 1 and 2 towards
Mycobacterium tuberculosis needs to be tested to verify if
a potential synergistic activity over API combinations exists that
consequently could lead to therapeutic advantages.
Fig. 7 Packing diagram for co-crystal 2.
Acknowledgements
P. G. thanks the Indian Institute of Science for a postdoctoral
fellowship. A. M. thanks CSIR for a JRF. G. R. D. thanks the
DST for the award of a J. C. Bose fellowship. We thank the
Rigaku Corporation, Tokyo, for their support through
a generous loan of a RigakuMercury375R/M CCD (XtaLAB
mini) diffractometer.
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Fig. 8 Close packing of molecules in co-crystal 2 showing the placement
of water in voids.
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This journal is ª The Royal Society of Chemistry 2011
CrystEngComm, 2011, 13, 4358–4364 | 4363