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author:("umesh, K.")
1.  Ethyl 5-oxo-4-phenyl-5,6-di­hydro-4H-1,3,4-oxadiazine-2-carboxyl­ate 
The asymmetric unit of title compound, C12H12N2O4, consists of two independent mol­ecules. In each mol­ecule, the oxadiazine ring has a flattened envelope conformation with the methyl­ene C atom as the flap atom, and the eth­oxy­carbonyl unit is in a syn-periplanar conformation with respect to the oxadiazine ring as indicated by O—C—C=O torsion angles of 1.9 (4) and 2.5 (4)°. The dihedral angles between the mean plane of the oxadiazine ring and the phenyl ring are 80.07 (13) and 42.98 (14)°. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds and stacked in a double-column along the a-axis direction.
PMCID: PMC4051085  PMID: 24940244
2.  N′-Benzoyl-5-methyl-1,3-diphenyl-1H-pyrazole-4-carbohydrazide 
In the title compound, C24H20N4O2, the pyrazole ring makes dihedral angles of 47.57 (10)° and 30.56 (11)° with its N-bound and C-bound phenyl groups, respectively. The C—N—N—C group that links the two carbonyls has a torsion angle of 81.5 (2)°. The torsion angles between the carbonyl groups and their adjacent pyrazole and phenyl rings are 125.89 (19) and 164.22 (17)°, respectively. In the crystal, pairs of mol­ecules are linked by N—H⋯O hydrogen bonds into R 2 2(10) ring motifs, which in turn link to form chains that propagate parallel to the c-axis direction.
PMCID: PMC3885042  PMID: 24454218
3.  5-Methyl-1,3-diphenyl-N-(5-phenyl-1,3,4-thia­diazol-2-yl)-1H-pyrazole-4-carboxamide 
The asymmetric unit of the title compound C25H19N5OS, contains two mol­ecules, A and B. In mol­ecule A, the dihedral angles between the pyrazole ring and the C-bound phenyl group, the N-bound phenyl group and the thia­diazole ring are 32.30 (14), 52.25 (14) and 34.94 (12)°, respectively. The corresponding angles in mol­ecule B are 33.32 (14), 50.67 (15), and 70.30 (12)°, respectively. In the crystal, the A and B mol­ecules are linked by pairs of N—H⋯N hydrogen bonds, generating R 2 2(8) loops. This dimer linkage is reinforced by two C—H⋯O hydrogen bonds and one C—H⋯N hydrogen bond.
PMCID: PMC3885020  PMID: 24454195
4.  Ethyl 5-methyl-3-phenyl­isoxazole-4-carboxyl­ate 
In the title compound, C13H13NO3, the dihedral angle between the phenyl and isoxazole rings is 43.40 (13)°. The eth­oxy­carbonyl group is rotated out of the plane of the isoxazole ring by 16.2 (13)°.
PMCID: PMC3685120  PMID: 23795139
5.  5-Methyl-3-phenyl­isoxazole-4-carb­oxy­lic acid 
In the title compound, C11H9NO3, the phenyl and isoxazole rings form a dihedral angle of 56.64 (8)°. The carb­oxy group is almost in the same plane as the isoxazole ring with a C—C—C—O torsion angle of −3.3 (2)°. In the crystal, pairs of O—H⋯O hydrogen bonds link the mol­ecules into head-to-head dimers. C—H⋯N hydrogen bonds and π–π stacking inter­actions between phenyl rings [centroid–centroid distance = 3.9614 (17)Å] link the dimers into a three-dimensional network.
PMCID: PMC3685054  PMID: 23795073
6.  3-(4-Meth­oxy­phen­yl)-5-methylisoxazole-4-carb­oxy­lic acid 
In the title compound, C12H11NO4, the dihedral angle between the benzene and isoxazole rings is 42.52 (8)°. The carb­oxy­lic acid group is close to being coplanar with the isoxazole ring [dihedral angle = 5.3 (2)°]. In the crystal, inversion dimers linked by pairs of O—H⋯O hydrogen bonds generate R 2 2(8) loops.
PMCID: PMC3588455  PMID: 23476573
7.  OA01.23. Impact of climate change on medicinal plants - A review 
Ancient Science of Life  2012;32(Suppl 1):S23.
Medicinal plants are highly valuable to human livelihood and the medicinal plant wealth of India is well recognised. Studies on possible effects of climate change on medicinal plants are particularly significant due to their value within traditional systems of medicine and as economically useful plants. There is evidence that climate change is causing noticeable effects on life cycles and distribution of the plant species. However, the effect of climate change on secondary metabolites in plants is not well understood. A need for research to improve our understanding of climatic effects on medicinal plants is stressed in the present article. An attempt is being made here to review the work so far done on this important issue with Indian perspective.
Reviews have been collected from different sources related to medicinal plants.
The impact of climate change with respect to medicinal plants has been discussed under the following heads. Effect of elevated CO2 on productivity and quality, Effect on threats to medicinal plants species, Adaptation measures for climate change and global warming, Mitigation measures to reduce emission of CO2/GHGs, Future strategies for research.
The impact of climate change on medicinal plants both cultivated and wild is very significant. The need of the hour is to have a focused research approach specially on the accumulation of secondary metabolites of health significance. The research on medicinal plants with respect to climate change is very sporadic and insignificant in comparison with other commercial crops. It is the high time that, these group of plants should not be left as they are potential sources of bio-molecules and neutraceuticles.
PMCID: PMC3800900
8.  (Z)-4-Benzyl­idene-3-methyl­isoxazol-5(4H)-one 
In the title compound C11H9NO2, the phenyl and isoxazole rings are almost coplanar, making a dihedral angle of 1.14 (9)°. This planarity is also assisted by an intra­molecular C—H⋯O hydrogen bond between the phenyl ring and the carbonyl O atom. In the crystal, weak C—H⋯O inter­actions generate a layered structure parallel to the ac plane.
PMCID: PMC3515194  PMID: 23284421
9.  (E)-N′-Hy­droxy-1,3-diphenyl-4,5-di­hydro-1H-pyrazole-5-carboximidamide 
In the mol­ecule of the title compound, C16H16N4O, the pyrazole ring makes dihedral angles of 8.52 (13) and 9.26 (12)° with the phenyl rings. The dihedral angle between the benzene rings is 1.86 (13)°. In the crystal, mol­ecules are linked into centrosymmetric dimers via pairs of O—H⋯N hydrogen bonds. Weak N—H⋯N inter­actions connect the dimers into a chain along the [100] direction. The pyrazole ring adopts a highly flattened envelope conformation.
PMCID: PMC3379259  PMID: 22719457
10.  6-Fluoro-2-(4-meth­oxy­phen­yl)imidazo[2,1-b][1,3]benzothia­zole 
The asymmetric unit of the title compound, C16H11FN2OS, comprises two independent mol­ecules in which the benzothia­zole rings are essentially planar, with maximum deviations of 0.038 (2) and 0.045 (3) Å. The central benzothia­zole ring makes dihedral angles of 4.87 (13) and 0.64 (12)° and 4.04 (12) and 3.67 (12)° with the two terminal phenyl rings in the two independent mol­ecules. In the crystal, mol­ecules are connected via weak inter­molecular C—H⋯O hydrogen bonds forming supra­molecular chains along the c axis.
PMCID: PMC3238924  PMID: 22199773
11.  Methyl (2Z)-2-(2-fluoro-4-meth­oxy­benzyl­idene)-5-(4-meth­oxy­phen­yl)-7-methyl-3-oxo-2,3-dihydro-5H-[1,3]thia­zolo[3,2-a]pyrimidine-6-carboxyl­ate 
The asymmetric unit of the title compound, C24H21FN2O5S, consists of two crystallographically independent mol­ecules. In each mol­ecule, the central dihydro­pyrimidine ring is significantly puckered and adopts a conformation which is best described as an inter­mediate between a boat and a screw boat. The least-squares planes of the dihydro­pyrimidine rings are almost coplanar with the fluoro-substituted benzene rings, making dihedral angles of 9.04 (7) and 6.68 (7)°, and almost perpendicular to the meth­oxy-substituted benzene rings with dihedral angles of 89.23 (7) and 88.30 (7)°. In the mol­ecular structure, S(6) ring motifs are formed by C—H⋯O and C—H⋯S hydrogen bonds. In the crystal, mol­ecules are linked into a three-dimensional network by inter­molecular C—H⋯O and C—H⋯F hydrogen bonds. The crystal structure is further stabilized by a C—H⋯π inter­action.
PMCID: PMC3212305  PMID: 22090962
12.  Antioxidant and Antimicrobial Activity of 5-methyl-2-(5-methyl-1,3-diphenyl-1H-pyrazole-4-carbonyl)-2,4-dihydro-pyrazol-3-one 
Cycloaddition of nitrile imines 4 generated in situ by the catalytic dehydrogenation of diphenyl hydrazones 3 using Chloramine-T (CAT) as oxidant in glacial acetic acid with enolic form of ethyl acetoacetate 5 afforded Ethyl 3-aryl-5-methyl-1-phenyl-1H-pyrazol-4-carboxylate 6 in 80% yield. The said pyrazoles 6 refluxed with 80% hydrazine hydrate using absolute alcohol as solvent for about 2–3 hours to produce the respective 5-methyl-1,3-diphenyl-1H-pyrazole-4-carboxylic acid hydrazide 7. The alcoholic solution of pyrazole acid hydrazides on heating with ethyl acetoacetate 5 to give the 5-methyl-2-(5-methyl-1,3-diphenyl-1H-pyrazole-4-carbonyl)-2,4-dihydro-pyrazol-3-one 8. The synthesized compounds were found to exhibit good antimicrobial and antioxidant activity as evaluated by 1,1-diphenyl-2-picryl Hydrazyl (DPPH) radical scavenging, reducing power and DNA protection assays.
PMCID: PMC3614796  PMID: 23675159
pyrazoles; antimicrobial; antioxidant

Results 1-12 (12)