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Two new crystalline polymorphs and an amorphous phase of the active curcuminoid ingredient in turmeric are reported. Curcumin polymorph 2 has higher dissolution rate and better solubility than the known polymorph 1.
2-Methyl-4-(4-methylpiperazin-1-yl)-10H-thieno[2,3-b][1,5]benzodiazepine, C(17)H(20)N(4)S, commonly known as olanzapine, is a psychotropic agent that belongs to the thienobenzodiazepine class of drugs. A new polymorph form IV was obtained upon attempted cocrystallization with nicotinamide in a 1:1 ratio from an ethyl acetate solution. Two butterfly-like… (More)
Eutectics are a long known class of multi-component solids with important and useful applications in daily life. In comparison to other multi-component crystalline solids, such as salts, solid solutions, molecular complexes and cocrystals, eutectics are less studied in terms of molecular structure organization and bonding interactions. Classically, a… (More)
The bioactive herbal ingredient curcumin was screened with pharmaceutically acceptable coformers to discover solid-state forms of high solubility. Mechano-chemical grinding of curcumin with cocrystal formers in a fixed stoichiometry ratio resulted in binary eutectic compositions of curcumin-coformer with nicotinamide (1:2), ferulic acid (1:1), hydroquinone… (More)
The antitumor prodrug temozolomide (TMZ) decomposes in aqueous medium of pH≥7 but is relatively stable under acidic conditions. Pure TMZ is obtained as a white powder but turns pink and then brown, which is indicative of chemical degradation. Pharmaceutical cocrystals of TMZ were engineered with safe coformers such as oxalic acid, succinic acid, salicylic… (More)
Nitrofurantoin (NF) drug is known to transform to a hydrate form in aqueous medium. The hydration stability and dissolution rate of a few cocrystals of NF were compared with that of its stable β polymorph and hydrate form II. Hydrogen bonding and molecular packing in the novel cocrystal structures were analyzed. Pharmaceutical cocrystals of NF with… (More)
The novel carboxamide-pyridine N-oxide synthon, sustained via N-H...O- hydrogen bonding and C-H...O interaction, is shown to assemble isonicotinamide N-oxide in a triple helix architecture and the same heterosynthon is exploited to synthesize cocrystals of barbiturate drugs with 4,4'-bipyridine N,N'-dioxide.
The carboxamide-pyridine N-oxide heterosynthon is sustained by syn(amide)N-H...O-(oxide) hydrogen bond and auxiliary (N-oxide)C-H...O(amide) interaction (Reddy, L. S.; Babu, N. J.; Nangia, A. Chem. Commun. 2006, 1369). We evaluate the scope and utility of this heterosynthon in amide-containing molecules and drugs (active pharmaceutical ingredients, APIs)… (More)
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… (More)
The crystallization of fluoroquinolone antibiotics norfloxacin and ciprofloxacin with carboxylic acids gave six new salts that were characterized by infrared spectroscopy, differential scanning calorimetry, X-ray powder diffraction, and single crystal X-ray diffraction. Five of these salts are hydrates with different levels of water content. The molecular… (More)