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author:("Kant, raji")
1.  Identification of 1,2,3,4,6-Penta-O-galloyl-β-d-glucopyranoside as a Glycine N-Methyltransferase Enhancer by High-Throughput Screening of Natural Products Inhibits Hepatocellular Carcinoma 
Glycine N-methyltransferase (GNMT) expression is vastly downregulated in hepatocellular carcinomas (HCC). High rates of GNMT knockout mice developed HCC, while overexpression of GNMT prevented aflatoxin-induced carcinogenicity and inhibited liver cancer cell proliferation. Therefore, in this study, we aimed for the identification of a GNMT inducer for HCC therapy. We established a GNMT promoter-driven luciferase reporter assay as a drug screening platform. Screening of 324 pure compounds and 480 crude extracts from Chinese medicinal herbs resulted in the identification of Paeonia lactiflora Pall (PL) extract and the active component 1,2,3,4,6-penta-O-galloyl-β-d-glucopyranoside (PGG) as a GNMT inducer. Purified PL extract and PGG induced GNMT mRNA and protein expression in Huh7 human hepatoma cells and in xenograft tumors. PGG and PL extract had potent anti-HCC effects both in vitro and in vivo. Furthermore, PGG treatment induced apoptosis in Huh7 cells. Moreover, PGG treatment sensitized Huh7 cells to sorafenib treatment. Therefore, these results indicated that identifying a GNMT enhancer using the GNMT promoter-based assay might be a useful approach to find drugs for HCC. These data also suggested that PGG has therapeutic potential for the treatment of HCC.
PMCID: PMC4881495  PMID: 27153064
glycine N-methyltransferase (GNMT); hepatocellular carcinomas (HCC); 1,2,3,4,6-penta-O-galloyl-β-d-glucopyranoside (PGG); sorafenib; high-throughput screening (HTS)
2.  Crystal structure of 4-[(2,4-di­chloro­phen­yl)(5-hy­droxy-3-methyl-1-phenyl-1H-pyrazol-4-yl)meth­yl]-5-methyl-2-phenyl-2,3-di­hydro-1H-pyrazol-3-one 
In the title compound C27H22Cl2N4O2, the pyrazol-5-ol ring makes a dihedral angle of 34.80 (11)° with the phenyl ring to which it is bound, while the pyrazolone ring is inclined at 34.34 (12)° to its attached phenyl ring. In the crystal, N—H⋯O and C—H⋯Cl hydrogen bonds link the mol­ecules into chains along [010]. Inter­molecular π–π inter­actions are observed between the pyrazolone ring and the phenyl ring bound to the pyrazol-5-ol ring system [centroid–centroid separation = 3.916 (2) Å].
PMCID: PMC4647350  PMID: 26594489
crystal structure; pyrazolone; hydrogen bonding; π–π inter­actions
3.  Crystal structure of ethyl 4-(2-chloro­phen­yl)-2-methyl-4H-pyrimido[2,1-b][1,3]benzo­thia­zole-3-carboxyl­ate 
In the title compound, C20H17ClN2O2S, the dihedral angle between the planes of the benzo­thia­zole fused ring system (r.m.s. deviation = 0.024 Å) and the chloro­benzene ring is 89.62 (12)°. The ester C—O—C—C side chain has an anti orientation [torsion angle = −155.2 (3)°]. In the crystal, weak aromatic π–π stacking inter­actions are observed between the phenyl and pyrimidine rings [centroid–centroid seperation = 3.666 (2) Å].
PMCID: PMC4555405  PMID: 26396895
crystal structure; pyrimido[2,1-b][1,3]benzo­thia­zole; ester; biological activity
4.  Crystal structure of 1-(4-fluoro­phen­yl)-4-(4-meth­oxy­phen­yl)-1H-1,2,3-triazole 
In the title compound, C15H12FN3O, the triazole ring forms dihedral angles of 30.57 (8) and 21.81 (9)° with the fluoro-substituted and meth­oxy-substituted benzene rings, respectively. The dihedral angle between the benzene rings is 51.53 (7)°. In the crystal, π–π inter­actions between the triazole rings [centroid–centroid seperations = 3.774 (2) and 3.841 (2) Å] form chains along [010].
PMCID: PMC4571383  PMID: 26396783
crystal structure; 1,2,3-triazole; π–π inter­actions
5.  Crystal structure of 15,16-ep­oxy-7β,9α-di­hydroxy­labdane-13(16),14-dien-6-one 
In the title mol­ecule, C20H30O4, both cyclo­hexane rings adopt chair conformations. In the crystal, mol­ecules are connected by O—H⋯O hydrogen bonds forming chains along [100]. In addtion, an intra­molecular O—H⋯O hydrogen bond forms an S(5) ring.
PMCID: PMC4518982  PMID: 26279920
crystal structure; 15,16-epoxy-7β,9α-dihydroxylabdane-13(16),14-dien-6-one; otostegiafruticosa; biological activity; hydrogen bonding
6.  Crystal structure of [1-(3-chloro­phen­yl)-5-hy­droxy-3-methyl-1H-pyrazol-4-yl](p-tol­yl)methanone 
In the title compound C18H15ClN2O2, the dihedral angles between the central pyrazole ring and the pendant chloro­benzene and p-tolyl rings are 17.68 (10) and 51.26 (12)°, respectively. An intra­molecular O—H⋯O hydrogen bond is observed, which closes an S(6) ring.
PMCID: PMC4420059  PMID: 25995904
crystal structure; 4-acyl­pyrazolone derivative; hydrogen bonding
7.  Crystal structure of N-[(2-hy­droxy­naphthalen-1-yl)(4-methyl­phen­yl)meth­yl]acetamide 
In the title mol­ecule, C20H19NO2, the naphthalene ring system subtends a dihedral angle of 82.50 (7)° with the benzene ring and an intra­molecular N—H⋯O hydrogen bond closes an S(6) ring. In the crystal, mol­ecules are linked by O—H⋯O hydrogen bonds, which generate C(8) chains propagating in the [010] direction. The crystal structure also features weak π–π inter­actions [centroid–centroid separation = 3.7246 (10) Å].
PMCID: PMC4438828  PMID: 26029431
crystal structure; naphthalene; acetamide; π–π inter­actions; hydrogen bonding
8.  Crystal structure of 2-methyl-4-[(thio­phen-2-yl)methyl­idene]-1,3-oxazol-5(4H)-one 
The asymmetric unit of the title compound, C9H7NO2S, contains two crystallographically independent mol­ecules (A and B). Both mol­ecules are almost planar [maximum deviations = 0.047 (1) and 0.090 (1) Å, respectively, for the S atoms] with the oxazole and thio­phene rings being inclined to one another by 2.65 (16)° in mol­ecule A and by 4.55 (15)° in mol­ecule B. In the crystal, the individual mol­ecules are linked via C—H⋯O hydrogen bonds, forming –A–B–A–B– chains along the [10-1] direction. The chains are linked via C—H⋯π and π–π inter­actions [inter­centroid distances = 3.767 (2) and 3.867 (2) Å] involving inversion-related oxazole and thio­phene rings in both mol­ecules, forming a three-dimensional structure.
PMCID: PMC4384586  PMID: 25878864
crystal structure; azlactones; 1,3-oxazol-5(4H)-one; hydrogen bonding; C—H⋯π and π–π inter­actions
9.  Crystal structure of bis­(3-bromo­pyridine-κN)bis­(O-ethyl di­thio­carbonato-κ2 S,S′)nickel(II) 
In the title mol­ecular complex, [Ni(C3H5OS2)2(C5H4BrN)2], the Ni2+ cation is located on a centre of inversion and has a distorted octa­hedral N2S4 environment defined by two chelating xanthate ligands and two monodentate pyridine ligands. The C—S bond lengths of the thio­carboxyl­ate group are indicative of a delocalized bond and the O—Csp 2 bond is considerably shorter than the O—Csp 3 bond, consistent with a significant contribution of one resonance form of the xanthate anion that features a formal C=O+ unit and a negative charge on each of the S atoms. The packing of the mol­ecules is stabilized by C—H⋯S and C—H⋯π inter­actions. In addition, π–π inter­actions between the pyridine rings [centroid-to-centroid distance = 3.797 (3) Å] are also present. In the crystal structure, mol­ecules are arranged in rows along [100], forming layers parallel to (010) and (001).
PMCID: PMC4331872  PMID: 25705471
Crystal structure; nickel complex; xanthate ligands; π–π inter­actions; crystal structure
10.  Conformation and crystal structures of 1-amino­cyclo­hexa­neacetic acid (β3,3Ac6c) in N-protected derivatives1  
The gauche conformation of backbone torsion angles (ϕ, θ) for β3,-Ac6c-OH is observed in the N-protected derivatives of 1-amino­cyclo­hexa­neacetic acid.
N-Protected derivatives of 1-amino­cyclo­hexa­neacetic acid (β3,3-Ac6c), namely Valeroyl-β3,3-Ac6c-OH [2-(1-pentanamidocyclohexyl)acetic acid, C13H23NO3], (I), Fmoc-β3,3-Ac6c-OH [2-(1-{[(9H-fluoren-9-yloxy)carbonyl]amino}cyclohexyl)acetic acid, C23H25NO4], (II), and Pyr-β3,3-Ac6c-OH {2-[1-(pyrazine-2-amido)cyclohexyl]acetic acid, C13H17N3O3}, (III), were synthesized and their conformational properties were determined by X-ray diffraction analysis. The backbone torsion angles (ϕ, θ) for β3,3-Ac6c-OH are restricted to gauche conformations in all the derivatives, with a chair conformation of the cyclo­hexane ring. In the crystal structure of (I), the packing of mol­ecules shows both carb­oxy­lic acid R 2 2(8) O—H⋯O and centrosymmetric R 2 2(14) N—H⋯O hydrogen-bonding inter­actions, giving rise to chains along the c-axis direction. In (II), centrosymmetric carb­oxy­lic acid R 2 2(8) O—H⋯O dimers are extended through N—H⋯O hydrogen bonds and together with inter-ring π–π inter­actions between Fmoc groups [ring centroid distance = 3.786 (2) Å], generate a layered structure lying parallel to (010). In the case of compound (III), carb­oxy­lic acid O—H⋯Npyrazine hydrogen bonds give rise to zigzag ribbon structures extending along the c-axis direction.
PMCID: PMC4257263  PMID: 25484721
crystal structure; disubstituted-β-amino acids; π–π inter­action; hydrogen bonds; conformation
11.  Crystal structure of (4Z)-1-(3,4-di­chloro­phen­yl)-4-[hy­droxy(4-methyl­phen­yl)methyl­idene]-3-methyl-4,5-di­hydro-1H-pyrazol-5-one 
The title compound, C18H14Cl2N2O2, crystallizes with two mol­ecules, A and B, in the asymmetric unit. In mol­ecule A, the dihedral angles between the central pyrazole ring and pendant di­chloro­benzene and p-tolyl rings are 2.18 (16) and 46.78 (16)°, respectively. In mol­ecule B, the equivalent angles are 27.45 (16) and 40.45 (18)°, respectively. Each mol­ecule features an intra­molecular O—H⋯O hydrogen bond, which closes an S(6) ring and mol­ecule A also features a C—H⋯O inter­action. In the crystal, weak C—H⋯π interactions and aromatic π–π stacking [shortest centroid–centroid separation = 3.707 (2) Å] generate a three-dimensional network.
PMCID: PMC4257223  PMID: 25484715
crystal structure; Schiff-base pyrazole derivative; hydrogen bonding; C—H⋯π inter­actions; aromatic π–π stacking
12.  Crystal structure of 5,5′-[(4-fluoro­phen­yl)methyl­ene]bis­[6-amino-1,3-di­methyl­pyrimidine-2,4(1H,3H)-dione] 
In the title mol­ecule, C19H21FN6O4, the dihedral angles between the benzene ring and essentially planar pyrimidine rings [maximum deviations of 0.036 (2) and 0.056 (2) Å] are 73.32 (7) and 63.81 (8)°. The dihedral angle between the mean planes of the pyrimidine rings is 61.43 (6)°. In the crystal, N—H⋯O hydrogen bonds link mol­ecules, forming a two-dimensional network parallel to (001) and in combination with weak C—H⋯O hydrogen bonds, a three-dimensional network is formed. Weak C—H⋯π inter­actions and π–π inter­actions, with a centroid–centroid distance of 3.599 (2) Å are also observed.
PMCID: PMC4257154  PMID: 25484692
crystal structure; uracil derivatives; biological activity; pyrimidine scaffolds; bis-uracil derivatives
13.  Crystal structure of 4-[(E)-(4-chloro­benzyl­idene)amino]-3-(2-methyl­benz­yl)-1H-1,2,4-triazole-5(4H)-thione 
In the title mol­ecule, C17H15ClN4S, the benzene rings form dihedral angles of 16.6 (1) and 77.2 (1)° with the triazole ring. The dihedral angle between the benzene rings is 86.6 (1)°. In the crystal, pairs of N—H⋯S hydrogen bonds form inversion dimers with graph-set notation R 2 2(8). Weak C—H⋯S hydrogen bonds link these dimers into layers parallel to (100). Weak intra­molecular C—H⋯S and C—H⋯N contacts are observed.
PMCID: PMC4186062  PMID: 25309199
crystal structure; Schiff base; 1,2,4-triazole; hydrogen bonding
14.  Crystal structure of (Z)-1-(3,4-dichlorophenyl)-3-methyl-4-[(naphthalen-1-yl­amino)(p-tolyl)methylidene]-1H-pyrazol-5(4H)-one 
The title Schiff base compound, C28H21Cl2N3O, was synthesized by the condensation of 1-(3,4-di­chloro­phen­yl)-3-methyl-4-(4-methyl­benzo­yl)-1H-pyrazol-5(4H)-one with 1-aminona­phthalene. The p-tolyl ring is normal to the pyrazole ring, with a dihedral angle of 88.02 (14)°, and inclined to the naphthalene ring system by 78.60 (12)°. The pyrazole ring is inclined to the naphthalene ring system and the di­chloro-substituted benzene ring by 63.30 (12) and 11.03 (13)°, respectively. The amino group and carbonyl oxygen atom are involved in an intra­molecular N—H⋯O hydrogen bond enclosing an S(6) ring motif. There is also a short C—H⋯O contact involving the carbonyl O atom and the adjacent benzene ring. In the crystal, mol­ecules are linked by C—H⋯π inter­actions, forming a three-dimensional structure.
PMCID: PMC4186144  PMID: 25309277
crystal structure; Schiff base; naphthalene; pyrazolone; pyrrole
15.  6-Amino-3-methyl-4-(3,4,5-tri­meth­oxy­phen­yl)-2,4-di­hydro­pyrano[2,3-c]pyrazole-5-carbo­nitrile 
In the title compound, C17H18N4O4, the dihedral angle between the benzene ring and 2,4-di­hydro­pyrano[2,3-c]pyrazole ring system is 89.41 (7)°. The pyran moiety adopts a strongly flattened boat conformation. In the crystal, mol­ecules are linked by N—H⋯N, N—H⋯O, C—H⋯N and C—H⋯O hydrogen bonds into an infinite two-dimensional network parallel to (110). There are π–π inter­actions between the pyrazole rings in neighbouring layers [centroid–centroid distance = 3.621 (1) Å].
PMCID: PMC4158517  PMID: 25249920
crystal structure
16.  Ethyl 6-amino-5-cyano-4-phenyl-2,4-di­hydro­pyrano[2,3-c]pyrazole-3-carboxyl­ate dimethyl sulfoxide monosolvate 
In the asymmetric unit of the title compound, C16H14N4O3·C2H6OS, there are two independent main mol­ecules (A and B) and two dimethyl sulfoxide solvent mol­ecules. In mol­ecule A, the pyran ring is in a flattened sofa conformation, with the sp 3-hydridized C atom forming the flap. In mol­ecule B, the pyran ring is in a flattened boat conformation, with the sp 3-hydridized C atom and the O atom deviating by 0.073 (3) and 0.055 (3) Å, respectively, from the plane of the other four atoms. The mean planes the pyrazole and phenyl rings form dihedral angles of 84.4 (2) and 84.9 (2)°, respectively, for mol­ecules A and B. In the crystal, N—H⋯O and N—H⋯N hydrogen bonds link the components of the structure into chains along [010]. In both solvent mol­ecules, the S atoms are disordered over two sites, with occupancy ratios of 0.679 (4):0.321 (4) and 0.546 (6):0.454 (6).
PMCID: PMC4120557  PMID: 25161577
18.  2-[4-(Piperidin-1-yl)-5H-chromeno[2,3-d]pyrimidin-2-yl]phenol 
In the title compound, C22H21N3O2, the pyrimidine ring is essentially planar [maximum deviation = 0.018 (2) Å] and forms dihedral angles of 22.70 (8) and 0.97 (7)°, respectively, with the fused benzene ring and the hy­droxy-substituted benzene ring. The piperidine ring has a chair conformation and the pyran ring has a flattened twist-boat conformation. The hy­droxy group was refined as disordered over two sets of sites in a 0.702 (4):0.298 (4) ratio. The disorder corresponds to a rotation of approxomiately 180° about the C—C bond connecting the phenol group to the pyrimidine ring and hence, both the major and minor components of disorder form intra­molecular O—H⋯N hydrogen bonds. In the crystal, pairs of weak C—H⋯π inter­actions form inversion dimers. In addition, π–π inter­actions are observed between the pyrimidine ring and the hy­droxy-substituted benzene ring [centroid–centroid separation = 3.739 (2) Å].
PMCID: PMC3998607  PMID: 24826150
19.  5-((Meth­oxy­imino)­{2-[(2-methyl­phen­oxy)meth­yl]phen­yl}meth­yl)-N-phenyl-1,3,4-oxa­diazol-2-amine 
In the title mol­ecule, C24H22N4O3, the plane of the oxa­diazole ring forms a dihedral angle of 32.41 (12)° with that of the phenyl ring and dihedral angles of 74.51 (10) and 56.38 (10)° with the planes of the benzene rings. In the crystal, pairs of N—H⋯N hydrogen bonds link molecules into inversion dimers featuring R 2 2(8) graph-set motifs.
PMCID: PMC3998470  PMID: 24765044
20.  4-Cyano-3-fluoro­phenyl 4-(hexa­dec­yl­oxy)benzoate 
In the title compound, C30H40FNO3, the dihedral angle between the benzene rings is 57.76 (7)°. The alkyl chain adopts an all-trans conformation. In the crystal, mol­ecules are linked by pairs of C—H⋯O hydrogen bonds, forming inversion dimers.
PMCID: PMC3998482  PMID: 24764965
21.  Dimethyl 2-[2-(2,4,6-tri­chloro­phen­yl)hydrazin-1-yl­idene]butane­dioate 
In the title compound, C12H11Cl3N2O4, the dihedral angle between the aromatic ring and the hydrazine (NH—N=C) grouping is 52.2 (3)°. The butanedioate groups exhibit planar conformations. An intra­molecular N—H⋯O hydrogen bond links the N—H group of the hydrazine to one of the meth­oxy groups of the butane­dioate moiety. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds and π–π inter­actions are also observed [centroid–centroid separation = 3.535 (1) Å].
PMCID: PMC3914063  PMID: 24526964
22.  5-(5′-Fluoro-2′-meth­oxy­biphenyl-3-yl)-1,3,4-oxa­diazol-2-amine 
In the title compound, C15H12FN3O2, the dihedral angles between the central benzene ring and the pendant benzene and oxa­diazole rings are 45.05 (13) and 15.60 (14)°, respectively. The C atom of the meth­oxy group is roughly coplanar with its attached ring [displacement = 0.178 (4) Å]. In the crystal, N—H⋯N hydrogen bonds link the mol­ecules into [010] chains. Weak C—H⋯π inter­actions are also observed.
PMCID: PMC3885053  PMID: 24454229
23.  Molecular Docking Study of Conformational Polymorph: Building Block of Crystal Chemistry 
The Scientific World Journal  2013;2013:309710.
Two conformational polymorphs of novel 2-[2-(3-cyano-4,6-dimethyl-2-oxo-2H-pyridin-1-yl)-ethoxy]-4,6-dimethyl nicotinonitrile have been developed. The crystal structure of both polymorphs (1a and 1b) seems to be stabilized by weak interactions. A difference was observed in the packing of both polymorphs. Polymorph 1b has a better binding affinity with the cyclooxygenase (COX-2) receptor than the standard (Nimesulide).
PMCID: PMC3821945  PMID: 24250264
24.  (Z)-3-Methyl-4-[1-(4-methyl­anilino)propyl­idene]-1-phenyl-1H-pyrazol-5(4H)-one 
In the title mol­ecule, C20H21N3O, the central pyrazole ring forms dihedral angles of 4.75 (9) and 49.11 (9)°, respectively, with the phenyl and methyl-substituted benzene rings. The dihedral angle between the phenyl and benzene rings is 51.76 (8)°. The amino group and carbonyl O atom are involved in an intra­molecular N—H⋯O hydrogen bond. In the crystal, π–π inter­actions are observed between benzene rings [centroid–centroid seperation = 3.892 (2) Å] and pyrazole rings [centroid–centroid seperation = 3.626 (2) Å], forming chains along [111]. The H atoms of the methyl group on the p-tolyl substituent were refined as disordered over two sets of sites in a 0.60 (4):0.40 (4) ratio.
PMCID: PMC3793766  PMID: 24109353
25.  (2Z)-3-(2,4-Di­chloro­phen­yl)-3-hy­droxy-N-phenyl­prop-2-ene­thio­amide 
In the title mol­ecule, C15H11Cl2NOS, the dihedral angle between the phenyl and benzene rings is 72.24 (1)°. In the crystal, pairs of N—H⋯S hydrogen bonds form dimers with twofold rotational symmetry. The dimers are connected by weak C—H⋯O hydrogen bonds, forming a two-dimensional network parallel to (001). An intra­molecular O—H⋯S hydrogen bond is also observed.
PMCID: PMC3770432  PMID: 24046717

Results 1-25 (101)