(2R)-4-[(9H-Fluoren-9-ylmeth-oxy)carbon-yl]-2-methyl-piperazin-1-ium chloride.

The synthesis of the title salt, C(20)H(23)N(2)O(2) (+)·Cl(-), was carried out with a precursor of known absolute configuration (R) and the X-ray analysis confirmed that the product retained the absolute configuration. In the crystal, the dominant packing motif is a chain running along [010] generated by N-H⋯Cl hydrogen bonding. C-H⋯O and C-H⋯Cl inter-actions are also observed.

Novel furosemide cocrystals and selection of high solubility drug forms.

Furosemide was screened in cocrystallization experiments with pharmaceutically acceptable coformer molecules to discover cocrystals of improved physicochemical properties, that is high solubility and good stability. Eight novel equimolar cocrystals of furosemide were obtained by liquid-assisted grinding with (i) caffeine, (ii) urea, (iii) p-aminobenzoic acid, (iv) acetamide, (v) nicotinamide, (vi) isonicotinamide, (vii) adenine, and (viii) cytosine. The product crystalline phases were characterized by powder x-ray diffraction, differential scanning calorimetry, infrared, Raman, near IR, and (13) C solid-state NMR spectroscopy.

Understanding of the mass spectrometric fragmentation pathways of a few potentially genotoxic haloaniline isomers in their protonated form by collision-induced dissociation.

Collision-induced dissociation (CID) mass spectra of a few haloaniline isomers, (chloroanilines, dichloroanilines, difluoroanilines, chloro-fluoroanilines and bromo-fluoroanilines) were characterized. The mass spectral behaviour of difluoroanilines was different from those of the corresponding regioisomers of the other haloanilines. For all ortho regioisomers except difluoroanilines, CID mass spectra resulted in hydrogen halide as well as halogen radical loss.