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1.  Tris(1,10-phenanthroline-κ2 N,N′)nickel(II) hexa­oxido-μ-peroxido-disulfate­(VI) N,N-dimethyl­formamide disolvate monohydrate 
The asymmetric unit of the title complex, [Ni(C12H8N2)3]S2O8·2C3H7NO·H2O, consists of a complex [Ni(phen)3]2+ cation and one isolated pds anion, with two DMF mol­ecules and one water mol­ecule as solvates (where phen is 1,10-phenanthroline, pds is the hexa­oxido-μ-peroxoido-di­sulf­ate dianion and DMF is dimethyl­formamide). The [Ni(phen)3]2+ cation is regular, with an almost ideal NiII bond-valence sum of 2.07 v.u. The group, as well as the water solvent mol­ecule, are well behaved in terms of crystallographic order, but the remaining three mol­ecules in the structure display different kinds of disorder, viz. the two DMF mol­ecules mimic a twofold splitting and the pds anion has both S atoms clamped at well-determined positions but with a not-too-well-defined central part. These peculiar behaviours are a consequence of the hydrogen-bonding inter­actions: the outermost SO3 parts of the pds anion are heavily connected to the complex cations via C—H⋯O hydrogen bonding, generating an [Ni(phen)3]pds network and providing for the stability of the terminal pds sites. Also, the water solvent mol­ecule is strongly bound to the structure (being a donor of two strong bonds and an acceptor of one) and is accordingly perfectly ordered. The peroxide O atoms in the pds middle region, instead, appear as much less restrained into their sites, which may explain their tendency to disorder. The cation–anion network leaves large embedded holes, amounting to about 28% of the total crystal volume, which are occupied by the DMF mol­ecules. The latter are weakly inter­acting with the rest of the structure, which renders them much more labile and, accordingly, prone to disorder.
PMCID: PMC3588241  PMID: 23476355
2.  Bis(acetato-κ2 O,O′)(4,4′-dimethyl-2,2′-bipyridine-κ2 N,N′)­zinc 
The mol­ecular structure of the title compound, [Zn(CH3COO)2(C12H12N2)], consists of isolated mol­ecules bis­ected by a twofold rotation axis which goes through the ZnII cation and halves the organic base through the central C—C bond. The ZnII ion is coordinated by two N atoms from one mol­ecule of the aromatic base and four O atoms from two bidentate, symmetry-related acetate anions, which coordinate asym­metrically [Zn—O distances of 2.058 (2) and 2.362 (3) Å], while the two Zn—N bond distances are equal as imposed by symmetry [2.079 (2) Å]. The crystal structure is supported by a number of weak C—H⋯O inter­actions and C—H⋯π contacts, with no π–π inter­actions present, mainly hindered by the substituent methyl groups and the relative mol­ecular orientation. The result is a three-dimensional structure in which each mol­ecule is linked to eight different neighbors.
PMCID: PMC3515128  PMID: 23284355
3.  3-Methyl-5-methyl­sulfanyl-1,3,4-thia­diazole-2(3H)-thione 
The title compound, C4H6N2S3, has two very similar mol­ecules per asymmetric unit. The nine non-H atoms in each mol­ecule are coplanar, both having comparable r.m.s. deviations of 0.002 Å. The main inter­est in the rather simple structure resides in a survey of very weak (in some cases, borderline) non-bonding inter­actions of various kinds, viz. S⋯S, C—H⋯π, π–π [centroid–centroid distance = 3.8958 (13) Å] and C—S⋯π [3.7271 (11) Å], which act as the major driving force for the arrangement of mol­ecules in the structure. The role of long, though highly directional, S⋯S contacts (d > 3.60 Å), and their relevance to the stability of the structure is discussed.
PMCID: PMC3470395  PMID: 23125808
4.  Benzyl 3-[(E)-(furan-2-yl)methyl­idene]-2-methyldithio­carbazate 
In the title compound, C14H14N2OS2, the furan ring exhibits rotational disorder over two orientations, with an occupancy ratio of 0.508 (7):0.492 (7). The furan and phenyl rings form dihedral angles of 8.2 (6) (major occupancy component), 14.8 (6) (minor occupancy component) and 73.65 (9)°, respectively, with the central residue (C4N2S2), indicating a twisted conformation for the mol­ecule. The methyl group and the thione S atom are syn and the conformation about the imine bond is E. In the crystal, C—H⋯π inter­actions involving the phenyl ring are observed.
PMCID: PMC3435764  PMID: 22969635
5.  Ammonium 4-meth­oxy­benzene­sulfonate 
The mol­ecular structure of the title compound, NH4 +·C7H7O4S−, is featureless [the methoxy C atom deviating 0.173 (6) Å from the phenyl mean plane] with inter­atomic distances and angles in the expected ranges. The main feature of inter­est is the packing mode. Hydro­philic (SO3 and NH4) and hydro­phobic (PhOCH3) parts in the structure segregate, the former inter­acting through a dense hydrogen-bonding scheme, leading to a well connected two-dimensional structure parallel to (100) and the latter hydro­phobic groups acting as spacers for an inter­planar separation of c/2 = 10.205 (2) Å. In spite of being aligned along [110], the benzene rings stack in a far from parallel fashion [viz. consecutive ring centers determine a broken line with a 164.72 (12)° zigzag angle], thus preventing any possible π–π inter­action.
PMCID: PMC3394020  PMID: 22798885
6.  Methyl 3-(2-hy­droxy­benzyl­idene)-2-methyl­dithio­carbazate 
In the title compound, C10H12N2OS2, the thione and S-methyl groups are syn. An intra­molecular bifurcated O—H⋯(S,N) hydrogen bond occurs.
PMCID: PMC3344635  PMID: 22590397
7.  5-Hy­droxy-3-methyl-5-phenyl-4,5-di­hydro-1H-pyrazole-1-carbothio­amide 
In the title compound C11H13N3OS, the aromatic ring and the dihydro­pyrazole ring are oriented orthogonally with respect to each other, making a dihedral angle of 89.92 (9)°. An intra­molecular O—H⋯S hydrogen bond occurs. In the crystal, weak N—H⋯N and N—H⋯S hydrogen bonds link the mol­ecules into a columnar stack propagating along the b axis.
PMCID: PMC3201317  PMID: 22065480
8.  Chloro­bis­(naphthalen-1-yl)phosphane 
In the title compound, C20H14ClP, the dihedral angle between the naphthyl rings is 81.77 (6)°. The crystal packing suggests weak π–π stacking inter­actions between the naphthyl rings in adjacent units [minimum ring centroid separation 3.7625 (13) Å].
PMCID: PMC3200679  PMID: 22059061
9.  H2S and NO cooperatively regulate vascular tone by activating a neuroendocrine HNO–TRPA1–CGRP signalling pathway 
Nature Communications  2014;5:4381.
Nitroxyl (HNO) is a redox sibling of nitric oxide (NO) that targets distinct signalling pathways with pharmacological endpoints of high significance in the treatment of heart failure. Beneficial HNO effects depend, in part, on its ability to release calcitonin gene-related peptide (CGRP) through an unidentified mechanism. Here we propose that HNO is generated as a result of the reaction of the two gasotransmitters NO and H2S. We show that H2S and NO production colocalizes with transient receptor potential channel A1 (TRPA1), and that HNO activates the sensory chemoreceptor channel TRPA1 via formation of amino-terminal disulphide bonds, which results in sustained calcium influx. As a consequence, CGRP is released, which induces local and systemic vasodilation. H2S-evoked vasodilatatory effects largely depend on NO production and activation of HNO–TRPA1–CGRP pathway. We propose that this neuroendocrine HNO–TRPA1–CGRP signalling pathway constitutes an essential element for the control of vascular tone throughout the cardiovascular system.
Nitric oxide (NO) and hydrogen sulphide (H2S) are two gaseous signalling molecules produced in tissues. Here the authors propose that NO and H2S react with each other to form nitroxyl (HNO), which activates the TRPA1 channel in nerve cells and triggers the release of the vasoactive peptide CGRP.
PMCID: PMC4104458  PMID: 25023795

Results 1-9 (9)