[N,N′‐Bis(3‐aminopropyl)ethylenediamine‐κ4N,N′,N′′,N′′′](trithiocyanurato‐κ2N,S)zinc(II) ethanol solvate

In the crystal structure of the title compound, [N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine‐κ⁴N,N′,N′′,N′′′][1,3,5‐triazine‐2,4,6(1H,3H,5H)‐tri­thionato(2−)‐κ²N,S]­zinc(II) ethanol sol­vate, [Zn(C₈H₂₂N₄)₂(C₃HN₃S₃)]·C₂H₆O, the Zn^II atom is octa­hedrally coordinated by four N atoms [Zn—N = 2.104 (2)–2.203 (2) Å] of a tetradentate N‐donor N,N′‐bis(3‐­amino­propyl)­ethyl­enedi­amine (bapen) ligand and by two S and N atoms [Zn—S = 2.5700 (7) Å and Zn—N = 2.313 (2) Å] of a tri­thio­cyanurate(2−) (ttcH²⁻) dianion bonded as a bidentate ligand in a cis configuration. The crystal structure of the compound is stabilized by a network of hydrogen bonds.     

Two new polymorphs of 4‐(N,N‐dimethyl­amino)­benzoic acid

Two new polymorphs of 4‐(N,N‐dimethyl­amino)­benzoic acid, C₉H₁₁NO₂, resulting from the attempted cocrystallization in ethanol of 4‐(N,N‐dimethyl­amino)­benzoic acid and a mixture of 3‐(N,N‐dimethyl­amino)­benzoic acid and 3‐(3‐pyrid­yl)‐2‐pyridone producing one polymorph, and a mixture of 3‐(N,N‐dimethyl­amino)­benzoic acid and 5‐meth­oxy‐3,3′‐bipyridine producing the second polymorph, have been crystallographically characterized. The primary inter­molecular O—H⋯O hydrogen bonds generate a dimeric acid–acid motif that is present in all three polymorphs.     

Hydro­gen‐bonded dimers in N‐(2‐nitro­phenyl­thio)­saccharin

In the title compound, 2‐(2‐nitro­phenyl­thio)‐1,2‐benzo­thia­zol‐3(2H)‐one 1,1‐dioxide, 2‐O₂NC₆H₄S(C₇H₄NO₃S) or C₁₃H₈N₂­O₅S₂, the planes of the saccharin and nitro­phenyl­thiol­ate portions are almost orthogonal. The mol­ecules are linked by C—H?O=S hydrogen bonds [C?O 3.308 (3) Å, H?O 2.44 Å and C—H?O 155°] into cyclic centrosymmetric R²₂(16) dimers, reinforced by aromatic π?π stacking interactions between the nitrated aryl rings.     

Two saccharinate complexes: [Mn(phen)2(sac)(H2O)]+·sac– and [Co(bipy)2(sac)(H2O)]+·sac–

The title saccharinate complexes, aqua[1,2‐benzisothiazol‐3(2H)‐onato 1,1‐dioxide‐N]bis(1,10‐phenanthroline‐N,N′)man­ganese(II) 1,2‐benz­isothia­zol‐3(2H)‐onate 1,1‐dioxide,[Mn(C₇H₄NO₃S)(C₁₂H₈N₂)₂(H₂O)](C₇H₄NO₃S), and aqua[1,2‐benz­iso­thiazol‐3(2H)‐onato 1,1‐dioxide‐N]­bis­(2,2′‐bi­pyri­dine‐N,N′)­cobalt(II) 1,2‐benz­iso­thia­zol‐3(2H)‐onate 1,1‐di­oxide, [Co­(C₇H₄NO₃S)­(C₁₀H₈N₂)₂­(H₂O)]­(C₇H₄NO₃S), have been prepared and their crystal structures determined at 150 K. The structure of the manganese complex consists of repeated alternating [Mn(phen)₂(sac)(H₂O)]⁺ cations and non‐coordinated saccharinate anions. The water molecule, bound to manganese as part of a slightly distorted octahedral arrangement, is hydrogen bonded to an O atom of the SO₂ group in the saccharinate counter‐ion. In contrast, the cobalt complex has one pseudo‐octahedral [Co(bipy)₂(sac)(H₂O)]⁺ cation, with the cobalt‐bound water molecule hydrogen bonded to the N atom of the accompanying free saccharinate anion.     

N‐(3H‐Thia­zol‐2‐yl­idene)­nitr­amine and N‐methyl‐N‐(thia­zol‐2‐yl)­nitr­amine

The geometries of the thia­zole ring and the nitr­amino groups in N‐(3H‐thia­zol‐2‐yl­idene)­nitr­amine, C₃H₃N₃O₂S, (I), and N‐­methyl‐N‐(thia­zol‐2‐yl)­nitr­amine, C₄H₅N₃O₂S, (II), are very similar. The nitr­amine group in (II) is planar and twisted along the C—N bond with respect to the thia­zole ring. In both structures, the asymmetric unit includes two practically equal mol­ecules. In (I), the mol­ecules are arranged in layers connected to each other by N—H⋯N and much weaker C—H⋯O hydrogen bonds. In the crystal structure of (II), the mol­ecules are arranged in layers bound to each other by both weak C—H⋯O hydrogen bonds and S⋯O dipolar interactions.     

Bis­(di‐μ‐acetato‐aqua{2‐[N‐ethyl‐N‐(2‐hydroxy‐4‐methyl­benzyl)­amino­methyl]‐1‐methyl­benz­imid­az­ole}­nickel)­nickel(II) tetra­hy­drate

The previously unknown title compound, tetra‐μ‐ace­tato‐1:2κ²O;1:2κ²O:O′;­2:3κ²O;­2:3κ²O:O′‐di­aqua‐1κO,3κO‐bis­(μ‐2‐{[N‐ethyl‐N‐(2‐hy­droxy‐5‐methylbenzyl)­am­ino]­methyl}‐1‐methyl‐1H‐benz­imid­az­ole)‐1κ³N³,N,O:2κO;3κ³N³,N,O:2κO‐tri­nickel(II) tetra­hy­drate, [Ni₃(C₁₈H₂₂N₃O)₂(C₂H₃O₂)₄(H₂O)₂]·­4H₂O, (I), is a centrosymmetric linear trinuclear nickel(II) complex, where the Ni atoms are in an octahedral coordination and the ligand heteroatoms act so as to model amino acid residues.     

Three N2‐benzoyl­oxybenz­amidines: sheet structures built from hard and soft hydrogen bonds and aromatic π–π stacking interactions

Molecules of the title compounds N²‐(benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₂, (I), N²‐(2‐hydroxy­benzoyl­oxy)­benz­ami­dine, C₁₄H₁₂N₂O₃, (II), and N²‐benzoyloxy‐2‐hydroxybenzamidine, C₁₄H₁₂N₂O₃, (III), all have extended chain conformations, with the aryl groups remote from one another. In (I), the mol­ecules are linked into chains by a single N—H⋯N hydrogen bond [H⋯N = 2.15 Å, N⋯N = 3.029 (2) Å and N—H⋯N = 153°] and these chains are linked into sheets by means of aromatic π–π stacking interactions. There is one intramolecular O—H⋯O hydrogen bond in (II), and a combination of one three‐centre N—H⋯(N,O) hydrogen bond [H⋯N = 2.46 Å, H⋯O = 2.31 Å, N⋯N = 3.190 (2) Å, N⋯O = 3.146 (2) Å, N—H⋯N = 138° and N—H⋯O = 154°] and one two‐centre C—H⋯O hydrogen bond [H⋯O = 2.46 Å, C⋯O = 3.405 (2) Å and C—H⋯O = 173°] links the mol­ecules into sheets. In (III), an intramolecular O—H⋯N hydrogen bond and two N—H⋯O hydrogen bonds [H⋯O = 2.26 and 2.10 Å, N⋯O = 2.975 (2) and 2.954 (2) Å, and N—H⋯O = 138 and 163°] link the molecules into sheets.     

2‐Acetamido‐N‐benz­yl‐2‐(methoxy­amino)acetamides: functionalized amino acid anticonvulsants

In the crystal structure of 2‐acetamido‐N‐benz­yl‐2‐(methoxy­amino)acetamide (3L), C₁₂H₁₇N₃O₃, the 2‐acetyl­amino­acetamide moiety has a linearly extended conformation, with an inter­planar angle between the two amide groups of 157.3 (1)°. In 2‐acetamido‐N‐benz­yl‐2‐[meth­oxy(meth­yl)­amino]­acetamide (3N), C₁₃H₁₉N₃O₃, the planes of the two amide groups inter­sect at an angle of 126.4 (4)°, resulting in a chain that is slightly more bent. The replacement of the methoxy­amino H atom of 3L with a methyl group to form 3N and concomitant loss of hydrogen bonding results in some positional/thermal disorder in the meth­oxy­(methyl)­amino group. In both structures, in addition to classical N—H⋯O hydrogen bonds, there are also weak non‐standard C—H⋯O hydrogen bonds. The hydrogen bonds and packing inter­actions result in planar hydro­philic and hydro­phobic areas perpendicular to the c axis in 3L and parallel to the ab plane in the N‐meth­yl derivative. Stereochemical comparisons with phenytoin have identified two O atoms and a phenyl group as mol­ecular features likely to be responsible for the anticon­vulsant activities of these compounds.     

Adducts of nickel(II) acetylacetonate chelating with heterocyclic bases: 3‐­cyanopyridine and 4‐cyanopyridine

In both title compounds, (acetyl­acetonato‐O,O′)­bis(3‐cyano­pyridine‐N)­nickel(II), (I), and (acetyl­acetonato‐O,O′)­bis(4‐cyanopyridine‐N)­nickel(II), (II), both [Ni(C₅­H₇O₂)₂(C₆H₄N₂)₂], the Ni^II atom, which is situated on a centre of symmetry, is octahedrally coordinated. Distances and angles for (I) and (II), respectively, are: Ni—O 2.009 (2)/2.016 (2) and 2.0110 (16)/2.0238 (18) Å, Ni—N 2.116 (3) and 2.179 (2) Å, O—Ni—O 91.86 (10) and 90.19 (7)°, and O—Ni—N 91.27 (11)/90.19 (11) and 89.65 (8)/90.79 (7)°.     

A new tricarbonyl­rhenium(I) compound incorporating the tridentate ligand N,N‐bis­picol­yl‐2‐ethano­lamine

The title compound, {[N,N‐bis­(2‐pyridylmeth­yl)­amino]­ethanol‐κ³N,N′,N′′}tricarbonyl­rhenium(I) bromide methanol solvate, [Re(C₁₄H₁₇N₃O)(CO)₃]Br·CH₄O, has been prepared in almost quantitative yield by reacting (NEt₄)₂[Re(CO)₃Br₃] with the ligand N,N‐bis­picol­yl‐2‐ethano­lamine in refluxing methanol. The X‐ray structure revealed that the Re(CO)₃N₃ coordination sphere is highly distorted from octa­hedral geometry and that the Re(CO)₃ core is facial. The coordinated ligand forms two five‐membered rings, with the pyridine rings in a butterfly formation. The OH group is not involved in metal coordination. The packing of the mol­ecule shows a network of classical O⋯H—O and Br⋯H—O, and non‐classical Br⋯H—C and O⋯H—C hydrogen bonds between the methanol solvate mol­ecules, the metal complex cations and the bromide anions.     

A bis­(acetyl­acetonato)­uranium(IV) complex of the Schiff base N,N′‐bis(3‐hydroxy­salicyl­idene)‐2‐methyl‐1,2‐propane­di­amine

The title complex, bis­(acetyl­acetonato‐κ²O,O′)[N,N′‐bis(3‐hydroxy‐2‐oxidobenzaldimino)‐2‐methyl‐1,2‐propane­di­amine‐κ⁴N,O,O′,N′]­uranium(IV) tetra­hydro­furan solvate, [U(C₁₈H₁₈N₂O₄)(C₅H₇O₂)₂]·C₄H₈O, is a rare example of a uranium(IV) complex with a compartmental Schiff base. The U atom is located in the N₂O₂ inner site of the hexadentate N,N′‐bis(3‐hydroxy‐2‐oxidobenzaldimino)‐2‐methyl‐1,2‐pro­pane­di­amine group and is bound also to the two O atoms of both acetyl­acetonate moieties, which results in a dodecahedral coordination environment. Centrosymmetric dimers are formed through intermolecular hydrogen bonds that link the terminal uncoordinated hydroxy groups to one another and to the O atoms of the acetyl­acetonate ligands.     

Bis­(saccharinato‐κN)zinc(II) com­plexes with N,N′‐bidentate 2‐amino­methyl­pyridine and 2‐amino­ethylpyridine

The structures of trans‐bis[2‐(amino­methyl)­pyridine‐κ²N,N′]­bis­(saccharinato‐κN)­zinc(II), [Zn(C₇H₄NO₃S)₂(C₆H₈N₂)₂], (I), and [2‐(amino­ethyl)­pyridine‐κ²N,N′]bis­(saccharinato‐κN)­zinc(II), [Zn(C₇H₄NO₃S)₂(C₇H₁₀N₂)], (II), exhibit octa‐ and tetrahedrally coordinated Zn^II atoms, respectively. The di­amine ligands behave as N,N′‐bidentate ligands, while saccharinate (sac) is coordinated through the N atom. In (I), the complex lies about an inversion centre with the Zn atom disordered and displaced by 0.256 (2) Å from a centre of symmetry towards a sac N atom. The crystal structure of (I) is stabilized by N—H⋯O hydrogen bonds and the crystal packing of (II) is determined by hydrogen bonding as well as weak π–π stacking interactions between the sac ligands.     

[N,N′‐Bis(5‐bromo­salicyl­idene)‐1,3‐di­amino­propane]­nickel(II) and [N,N′‐­bis(5‐chloro­salicyl­idene)‐1,3‐­di­amino­propane]copper(II)

The title compounds, {4,4′‐di­bromo‐2,2′‐[1,3‐propane­diyl­bis(nitrilo­methyl­idyne‐N)]­diphenolato‐O,O′}nickel(II), [Ni(C₁₇­H₁₄­Br₂­N₂O₂)], and {4,4′‐di­chloro‐2,2′‐[1,3‐pro­pane­diyl­bis­(ni­trilo­methyl­idyne‐N)]­di­phen­ol­ato‐O,O′}­copper(II), [Cu­(C₁₇­H₁₄­Cl₂­N₂O₂)], lie on crystallographic twofold axes. In both structures, the metal coordination sphere is a tetrahedrally distorted square plane formed by the four‐coordinate N₂O₂ donor set of the Schiff base imine–phenol ligands. In the Ni compound, the Ni—O and Ni—N distances are 1.908 (3) and 1.959 (4) Å, respectively, while in the Cu compound, the Cu—O and Cu—N distances are 1.907 (2) and 1.960 (2) Å, respectively. The two Schiff base moieties, which themselves are nearly planar, are inclined at an angle of 29.26 (7)° for the Ni compound and 29.26 (5)° for the Cu compound.     

catena‐Poly­[[trans‐bis­(ethane‐1,2‐di­amine‐κ2N,N′)copper(II)]‐μ‐di­thion­ato‐κ2O:O′] and trans‐di­aqua­bis­(propane‐1,3‐di­amine‐κ2N,N′)copper(II) di­thionate

In title an­hydro­us catena‐poly­[[trans‐bis­(ethane‐1,2‐di­amine‐κ²N,N′)copper(II)]‐μ‐di­thionato‐κ²O:O′], [Cu(S₂O₆)(C₂H₈N₂)₂]_n or [{H₂N(CH₂)₂NH₂}₂Cu(O·O₂SSO₂·O)]_∞, successive Cu atoms are bridged by a single doubly charged di­thionate group, forming a one‐dimensional polymer with inversion centres at the metal atoms and the mid‐point of the S—S bond [Cu—O = 2.5744 (15) Å]. In title (hydrated) trans‐di­aqua­bis­(propane‐1,3‐di­amine‐κ²N,N′)copper(II) di­thionate, [Cu(C₃H₁₀N₂)₂(H₂O)₂](S₂O₆) or [{H₂N(CH₂)₃NH₂}₂Cu(OH₂)₂](S₂O₆), both ions have imposed 2/m symmetry. The `axial' anion components are displaced by a pair of water ligands [Cu—O = 2.439 (3) Å], the shorter Cu—O distance being compensated by the lengthened Cu—N distance [2.0443 (18), cf. 2.0100 (13) and 2.0122 (16) Å].     

A novel one‐dimensional coordination polymer with Cd2+ and diethylenetriaminepentaacetic acid

catena‐Poly­[[[bis­[di­aqua(4,4′‐bi­pyridine)­cadmium(II)]‐bis­[μ‐(N′′‐carboxy­methyl­diethyl­enetri­amine‐N,N,N′,N′′‐tetra­ace­ta­to)­cadmium(II)]]‐μ‐4,4′‐bi­pyridine] tetradecahydrate], [Cd₄­(C₁₄H₁₉N₃O₁₀)₂(C₁₀H₈N₂)₃(H₂O)₄]·14H₂O or [Cd₄(HD­TPA)₂(BPY)₃(H₂O)₄]·14H₂O, where BPY is 4,4′‐bi­pyridine and HDTPA^4? is N′′‐carboxy­methyl­diethyl­enetri­amine‐N,N,N′,N′′‐tetra­acetate, consists of a one‐dimensional coordination polymer formed from a secondary building unit which comprises four Cd centres. The chain structure of the title compound was obtained by the use of a multidentate organic ligand, N,N,N′,N′′,N′′‐diethyl­enetri­amine­penta­acetic acid (H₅DTPA), which forms multiple chelate rings with the Cd metal centres. An extended network is formed via hydrogen bonds.     

Two N‐ortho‐nitro­benzene­sulfonyl α,α‐disubstituted amino acid adducts

The carboxy group of 2‐methyl‐N‐[(2‐nitrophenyl)sulfonyl]­alanine, C₁₀H₁₂N₂O₆S, forms centrosymmetric hydrogen‐bonded dimers with an O?O distance of 2.629 (2) Å and an intramolecular N—H?O(nitro) hydrogen bond N?O distance of 2.823 (2) Å. 1‐[(2‐Nitro­phenyl)­sulfonyl­amino]­cyclo­hexane­carboxyl­ic acid, C₁₃H₁₆N₂O₆S, has Z′ = 2 and forms similar interactions.     

A donor–acceptor compound composed of a di­nuclear zinc(II) complex of a Robson macro­cycle with 8‐methyl­quino­line

A donor–acceptor compound, di­aqua‐1κO,2κO‐[μ‐11,23‐dimethyl‐3,7,15,19‐tetra­aza­tri­cyclo­[19.3.1.1^9,13]hexacosa‐1(25),2,7,9,11,13(26),14,19,21,23‐decaene‐25,­26‐diolato‐1κ⁴N³,N⁷,O²⁵,O²⁶:­2κ⁴N¹⁵,N¹⁹,O²⁵,O²⁶]­dizinc(II) diperchlorate bis(8‐methyl­quinoline) ethanol disolvate, [Zn₂(C₂₄H₂₆N₄O₂)(H₂O)₂](ClO₄)₂·2C₁₀H₉N·2C₂H₆O, obtained by the reaction of a dinuclear zinc(II) complex of a Robson macrocycle (acceptor) and 8‐methyl­quinoline (donor), lies about an inversion centre and the coordination about the unique Zn atom is a distorted square pyramid. The fifth coordination site is occupied by the water mol­ecule, Zn—O = 2.016 (2) Å, and the average macrocyclic Zn—O and Zn—N distances are 2.059 (6) and 2.059 (3) Å, respectively.     

Novel heterocyclic inhibitors of matrix metalloproteinases: three 6H‐1,3,4‐thiadiazines

The title compounds, (2S)‐N‐[5‐(4‐chloro­phenyl)‐2,3‐di­hydro‐6H‐1,3,4‐thia­diazin‐2‐yl­idene]‐2‐[(phenyl­sulfonyl)­amino]­pro­pan­amide, C₁₈H₁₇ClN₄O₃S₂, (I), (2R)‐N‐[5‐(4‐fluoro­phenyl)‐6H‐1,3,4‐thia­diazin‐2‐yl]‐2‐[(phenyl­sulfonyl)amino]­propan­amide, C₁₈H₁₇FN₄O₃S₂, (II), and (2S)‐N‐[5‐(5‐chloro‐2‐thienyl)‐6H‐1,3,4‐thia­diazin‐2‐yl]‐2‐[(phenyl­sulfonyl)­amino]­propan­amide, C₁₆H₁₅ClN₄O₃S₃, (III), are potent inhibitors of matrix metalloproteinases. In all three compounds, the thia­diazine ring adopts a screw‐boat conformation. The mol­ecules of compound (I) show a short intramolecular N_Ala—H?N_exo hydrogen bond [N?N 2.661 (3) Å] and are linked into a chain along the c axis by N_endo—H?S_endo and N_endo—H?O_Ala hydrogen bonds [N?S 3.236 (3) and N?O 3.375 (3) Å] between neighbouring mol­ecules. In compound (II), the mol­ecules are connected antiparallel into a chain along the a axis by N_exo—H?O_Ala and N_Ala—H?N_endo hydrogen bonds [N?O 2.907 (6) and N?N 2.911 (6) Å]. The mol­ecules of compound (III) are dimerized antiparallel through N_exo—H?N_endo hydrogen bonds [N?N 2.956 (7) and 2.983 (7) Å]. The different hydrogen‐bonding patterns can be explained by an amido–imino tautomerism (prototropic shift) shown by different bond lengths within the 6H‐1,3,4‐thia­diazine moiety.     

{Bis­[2‐(2‐oxido‐1‐naphthylmethylidene­amino)­phenyl] disulfide}chloroiron(III)

The crystal structure of the title compound, {bis­[2‐(2‐oxido‐2‐naphthyl­idene­amino)­phenyl] di­sulfide‐κ⁵O,N,S,N′,O′}chloroiron(III), [FeCl(C₃₄H₂₂N₂O₂S₂)], has been determined. The structure consists of monomeric iron(III) complexes with distorted octahedral coordination. The di­sulfide functions as a pentadentate ligand and the Fe^III atom is coordinated through two N, two O and one S atom, and one chloride ion. The distance between the second S atom and the Fe^III atom is a non‐bonding 3.8473 (14) Å.     

Comparative X‐ray study of three nickel(II)–thio­cyanate compounds

Three cis nickel–di­thio­cyanate (SCN) complexes with different N,N′‐bidentate bases have been prepared and their crystal structures determined: bis(2,2′‐bi­pyridine‐N,N′)­bis­(thio­cyan‐­ato‐N)­nickel(II), [Ni(SCN)₂­(C₁₀H₈N₂)₂], bis(1,10‐phen­anthroline‐N,N′)­bis­(thio­cyanato‐N)­nickel(II), [Ni(SCN)₂­(C₁₂H₈N₂)₂], and bis(2,9‐di­methyl‐1,10‐phenanthroline‐N,N′)­bis­(thiocyanato‐N)nickel(II) mono­hydrate, [Ni(SCN)₂­(C₁₂H₈N₂)₂]·H₂O. Distortions due to ligand size are discussed.