5-Bromo-1,2,4-triazolo[1,5-a]pyrimidine

In the title compound, C5H3BrN4, the almost planar triazolopyrimidine ring system (r.m.s. deviation = 0.014 Å) carries a bromo substituent at the 5-position. In the crystal, C—H...N hydrogen bonds form inversion dimers enclosingR22(8) rings and also link molecules intoC(5) chains along thec-axis direction. Br...N halogen bonds [3.185 (4) Å], π–π stacking interactions, centroid-to-centroid separation [3.663 (3) Å] and C—Br...π contacts [Br...Cg= 3.7881 (17) Å] are also found and combine with the C—H...N hydrogen bonds to stack the molecules along thea-axis direction.

5-(2-Ethoxy-4-fluorophenyl)-1,2,4-triazolo[1,5-a]pyrimidine

In the title compound, C13H11FN4O, the dihedral angle between the triazolopyrimidine ring system and fluorophenyl ring is 39.16 (12)°. In the crystal, C—H...N hydrogen bonds link the molecules resulting inR22(8) ring motifs andC(8) chain motifs.

Ethyl (naphthalen-2-yloxy)acetate

In the title compound, C14H14O3, the dihedral angle between the naphthyl ring system and the side chain is 9.00 (14)°, and the ethoxy chain adopts an extended conformation [C—O—C—C = 176.0 (3)°]. There are no directional interactions in the crystal beyond normal van der Waals contacts.

4-Chloro-1-[2-(2-chlorophenyl)ethyl]-2-nitrobenzene

In the title compound, C14H11Cl2NO2, the dihedral angle between the phenyl rings is 8.60 (17)° and the nitro group makes a dihedral anle of 29.4 (4)° with its attached ring. The crystal structure features C—H...O hydrogen bonds and π–π interactions.

2-[(5-Amino-1,3,4-thiadiazol-2-yl)sulfanyl]-N-(2,4,5-trichlorophenyl)acetamide

In the title compound, C10H7Cl3N4OS2, the dihedral angle between the trichlorobenzene and thiadiazole rings is 29.26 (17)°. In the crystal, molecules are connected by N—H...O and C—H...O hydrogen bonds, forming chains propagating along [001]. The chains are linkedviaN—H...N hydrogen bonds to form slabs parallel to (100).

Ethyl 1-benzyl-2-(3-chlorophenyl)-1H-benzimidazole-5-carboxylate

In the title compound, C23H19ClN2O2, the dihedral angles between the imidazole ring system and the chlorobenzene and phenyl rings are 48.05 (14) and 82.53 (15)°, respectively. In the crystal, inversion dimers linked by pairs of C—H...O hydrogen bonds generateR22(22) loops. Weak C—H...π and π–π stacking interactions are also observed.

5-(2,4-Dichlorophenoxy)-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde

In the crystal structure of the title compound, C17H12Cl2N2O2, the pyrazole ring makes dihedral angles of 65.0 (2) and 43.9 (2)° with the dichlorophenyl and phenyl rings, respectively. The dihedral angle between the chlorophenyl and phenyl rings is 59.1 (2)°. In the crystal, the molecules are linked by C—H...O hydrogen bonds and weak C—Cl...π and C—H...π interactions, generating a three-dimensional network.

2-[(5-Amino-1,3,4-thiadiazol-2-yl)sulfanyl]-N-(4-chlorophenyl)acetamide

In the title compound, C10H9ClN4OS2, the dihedral angle between the planes of the chlorophenyl and thiadiazole groups is 32.93 (16)°. The molecules are connected through intermolecular N—H...N and N—H...O hydrogen bonds. An N—H...N hydrogen bond formsR22(8) ring motifs.

Ethyl 2-(4-cyanophenyl)-1-(4-fluorobenzyl)-1H-benzo[d]imidazole-5-carboxylate

The title benzimidazole derivative, C24H18FN3O2, is T-shaped, with the 4-cyanobenzene and 4-fluorobenzyl rings inclined to the imidazole ring system by 32.89 (10) and 83.63 (10)°, respectively, and by 89.00 (12)° to one another. The terminal methyl group of the ethylcarboxylate group is disordered over three sites and was refined with a fixed occupancy ratio of 1/3:1/3:1/3. In the crystal, molecules are essentially linked by offset π–π interactions, involving inversion-related imidazole rings [inter-centroid distance = 3.763 (1) Å], and stack along theb-axis direction.

Comparative evaluation of intrathecal morphine and intrathecal dexmedetomidine in patients undergoing gynaecological surgeries under spinal anaesthesia: A prospective randomised double blind study

BACKGROUND AND AIMS

Inrathecal opioids like morphine added to local anaesthetic agents have been found to be effective in achieving prolonged post-operative analgesia. Intrathecal dexmedetomidine may be devoid of undesirable side effects related to morphine and hence, this study was designed to evaluate analgesic efficacy, haemodynamic stability and adverse effects of both these adjuvants in patients undergoing gynaecological surgeries.

METHODS

This was a prospective, randomised, double blind study involving 25 patients in each group. Group M received 15 mg of 0.5% hyperbaric bupivacaine with 250 μg of morphine while Group D received 15 mg of 0.5% hyperbaric bupivacaine with 2.5 μg of dexmedetomidine. Characteristics of spinal block, time for first rescue analgesic and total dose of rescue analgesics were noted. Vital parameters and adverse effects were noted perioperatively. Data analysis was done with independent two sample t-test and Mann-Whitney U test.

RESULTS

Time for first rescue analgesic (P = 0.056) and total analgesic demand were similar in both groups. Duration of sensory (P = 0.001) and motor (P = 000) block was significantly higher in dexmedetomidine group. Itching was noticed in 36% and nausea in 52% of patients in the morphine group, either of which was not seen in dexmedetomidine group.

CONCLUSION

Intrathecal dexmedetomidine produces prolonged motor and sensory blockade without undesirable side effects but intraoperative hypotension was more frequent in dexmedetomidine group.

Ethyl 2-(3,5-difluorophenyl)quinoline-4-carboxylate: a second triclinic polymorph

The title compound, C18H13F2NO2, is a polymorph of the structure reported by Sunithaet al.[Acta Cryst.(2015), E71, o341–o342]. Both compounds crystallize in the triclinic space groupP-1. The principal difference between the two polymorphs lies in the orientation of the carboxylate substituents with respect to the planes of the quinoline ring systems. In the crystal, the packing features C—H...O hydrogen bonds together with short C—F...π and π–π interactions [inter-centroid distances of 3.8199 (11), 3.6825 (12) and 3.8722 (13) Å].

Tramadolium 2-chlorobenzoate

In the title molecular salt, C16H26NO2+·C7H4ClO2−, {systematic name: [2-hydroxy-2-(3-methoxyphenyl)cyclohexylmethyl]dimethylammonium 2-chlorobenzoate}, the cyclohexane ring of the cation exhibits a chair conformation with the aromatic and amine substituents in equatorial orientations and the hydroxyl group in an axial orientation. In the anion, the dihedral angle between the aromatic ring and the carboxylate group is 39.16 (13)°. In the crystal, the cations are linked to the anions by O—H...O, N—H...O and C—H...O hydrogen bonds, generating [010] chains. Further C—H...O and C—H...π interactions are also observed, which link the chains into a three-dimensional framework.

Crystal structure of 4-[(E)-(4-fluoro-benzyl-idene)amino]-3-methyl-1H-1,2,4-triazole-5(4H)-thione

The title compound, C10H9FN4S, crystallizes with two mol-ecules (A and B) in the asymmetric unit. The dihedral angle between the planes of the trizole and fluoro-benzene rings is 7.3 (3)° in mol-ecule A and 41.1 (3)° in mol-ecule B. Mol-ecule A features an intra-molecular C-H⋯S hydrogen bond, which closes an S(6) ring. In the crystal, A+B dimers linked by pairs of N-H⋯S hydrogen bonds occur, generating R 2 (2)(8) loops. Weak π-π stacking contacts [centroid-centroid separation = 3.739 (6) Å] are also observed.

Crystal structure of (E)-3-(4-hy-droxy-benz-yl)-4-{[4-(methyl-sulfan-yl)benzyl-idene]amino}-1H-1,2,4-triazole-5(4H)-thione

In the title compound, C17H16N4OS2, the triazole and methyl-thio-benzyl-idene rings are nearly coplanar, making a dihedral angle of 6.52 (12)°. An intra-molecular C-H⋯S hydrogen bond forms an S(6) ring motif. The hy-droxy-benzyl ring is almost normal to the triazole and methyl-thio-benzyl-idene rings, making dihedral angles of 78.56 (12) and 84.79 (11)°, respectively. In the crystal, mol-ecules are linked through O-H⋯N and N-H⋯O hydrogen bonds, forming layers parallel to the ac plane. The layers are linked via C-H⋯N hydrogen bonds, forming a three-dimensional structure. In addition, a short π-π inter-action is observed [inter-centroid distance = 3.764 (3) Å], involving inversion-related methyl-thio-benzyl-idene rings.

Crystal structure of {[2-hy-droxy-2-(3-meth-oxy-phen-yl)cyclo-hex-yl]meth-yl}di-methyl-ammonium benzoate

The title compound, C16H26NO2 (+)·C7H5O2 (-), is a benzoate salt of the painkiller Tramadol. The six-membered cyclo-hexane ring of the cation adopts a slightly distorted chair conformation and carries OH and 3-meth-oxy-phenyl substituents at the 2-position and a protonated methyl-aza-niumylmethyl group at the 3-position. In addition, a weak intra-molecular C-H⋯O hydrogen bond is observed in the cation. In the crystal, weak O-H⋯O, N-H⋯O and C-H⋯O hydrogen bonds link the components into chains along [010]. A C-H⋯π contact is also observed.

High prevalence of undiagnosed diabetes among tuberculosis patients in peripheral health facilities in Kerala

SETTING

Two tertiary care hospitals and 12 peripheral health institutions (PHIs) in Trivandrum, Kerala, India.

OBJECTIVE

To determine factors associated with the prevalence of diabetes mellitus (DM) among tuberculosis (TB) patients and examine differences in the proportion of new DM cases among TB patients diagnosed at tertiary care centres and PHIs.

DESIGN

A descriptive study: TB patients diagnosed during March-September 2012 were screened for known DM. Those with unknown DM status were tested for random blood glucose and fasting blood glucose (FBG); FBG ≥ 126 mg/dl was diagnosed as new DM.

RESULTS

Of 920 TB patients, 689 (72%) were male and the mean (standard deviation) age was 47.6 (16.4) years. Of these, 298 (32.4%) were diabetic: 235 (26%) had previously known DM and 63 (7%) were newly diagnosed. During the screening at PHIs and tertiary care hospitals, respectively 30/183 (16.4%) and 33/737 (4.5%) were newly diagnosed with DM (OR 3.71; 95%CI 2.17-6.32). Overall, age >50 years and pulmonary tuberculosis were independently associated with a higher prevalence of diabetes.

CONCLUSION

As nearly one in three TB patients had DM, we recommend that TB patients should be routinely screened for DM in Kerala. As the proportion of new DM was higher among TB patients diagnosed at PHIs, we would recommend that specific attention and investment be directed to PHIs.

Crystal structure of ATP-binding subunit of an ABC transporter from Geobacillus kaustophilus

The ATP binding cassette (ABC) transporters, represent one of the largest superfamilies of primary transporters, which are very essential for various biological functions. The crystal structure of ATP-binding subunit of an ABC transporter from Geobacillus kaustophilus has been determined at 1.77 Å resolution. The crystal structure revealed that the protomer has two thick arms, (arm I and II), which resemble 'L' shape. The ATP-binding pocket is located close to the end of arm I. ATP molecule is docked into the active site of the protein. The dimeric crystal structure of ATP-binding subunit of ABC transporter from G. kaustophilus has been compared with the previously reported crystal structure of ATP-binding subunit of ABC transporter from Salmonella typhimurium.

Crystal structures of type IIIH NAD-dependent D-3-phosphoglycerate dehydrogenase from two thermophiles

In the L-Serine biosynthesis, D-3-phosphoglycerate dehydrogenase (PGDH) catalyzes the inter-conversion of D-3-phosphoglycerate to phosphohydroxypyruvate. PGDH belongs to 2-hydroxyacid dehydrogenases family. We have determined the crystal structures of PGDH from Sulfolobus tokodaii (StPGDH) and Pyrococcus horikoshii (PhPGDH) using X-ray diffraction to resolution of 1.77Å and 1.95Å, respectively. The PGDH protomer from both species exhibits identical structures, consisting of substrate binding domain and nucleotide binding domain. The residues and water molecules interacting with the NAD are identified. The catalytic triad residues Glu-His-Arg are highly conserved. The residues involved in the dimer interface and the structural features responsible for thermostability are evaluated. Overall, structures of PGDHs with two domains and histidine at the active site are categorized as type IIIH and such PGDHs structures having this type are reported for the first time.

Bis(2-bromo-benz-yl) ether

In the title compound, C₁₄H₁₂Br₂O, the dihedral angle between the aromatic rings is 2.7 (3)° and the Br atoms lie on the same side of the mol­ecule. No inter­molecular inter­actions occur in the crystal beyond van der Waals contacts.

5-(4-Chloro-phen-oxy)-3-methyl-1-phenyl-1H-pyrazole-4-carbaldehyde

In the title compound, C₁₇H₁₃ClN₂O₂, the phenyl and chloro­benzene rings are inclined to the central pyrazole ring at 40.84 (9) and 65.30 (9)°, respectively. In the crystal, pairs of C—H⋯π inter­actions link the mol­ecules into inversion dimers and C—H⋯O hydrogen bonds link these dimers into columns extended in [010]. The crystal packing exhibits short inter­molecular O⋯Cl contacts of 3.0913 (16) Å.

2-Nitro-benzyl methane-sulfonate

In the title compound, C₈H₉NO₅S, the dihedral angle between the benzene ring and the nitro group is 5.86 (15)° and the C—C—O—S group adopts an anti conformation [torsion angle = −168.44 (15)°]. In the crystal, mol­ecules are linked by C—H⋯O hydrogen bonds, generating a three-dimensional network.

4-(4-Methyl-phen-yl)-2-(prop-2-yn-1-yl)phthalazin-1(2H)-one

In the title compound, C₁₈H₁₄N₂O, the dihedral angle between the methyl­phenyl ring and the phthalazone ring system (r.m.s. deviation = 0.034 Å) is 53.93 (9)°. In the crystal, mol­ecules are connected by C—H⋯O hydrogen bonds, forming chains along [101]. The chains are linked by π–π inter­actions [centroid–centroid distance 3.6990 (12) Å], forming layers parallel to (10-1).

6,7-Dimethoxy-2,4-diphenylquinoline

In the title structure of the title compound, C₂₃H₁₉NO₂, two conformationally similar mol­ecules (A and B) comprise the asymmetric unit. The dihedral angle between phenyl rings bridged by the quinoline moiety are 76.25 (8)° in mol­ecule A and 70.39 (9)° in mol­ecule B. In the crystal, the independent mol­ecules are connected by C—H⋯O hydrogen bonds and the resulting dimeric aggregates are linked by π–π [inter-centroid distance = 3.7370 (8) Å] and C—H⋯π inter­actions, forming a three-dimensional architecture.

(E)-N′-[4-(Dimethylamino)benzylidene]-2-(4-methylphenoxy)acetohydrazide

In the title compound, C₁₈H₂₁N₃O₂, the dihedral angle between the benzene rings is 68.85 (11)°. In the crystal, the mol­ecules are linked by C—H⋯O and N—H⋯O hydrogen bonds, as well as weak C—H⋯π contacts, forming a three-dimensional supra­molecular architecture.