Moxifloxacinium chloride–water–methanol (2/1/1), a novel anti­bacterial agent

Moxifloxacin, a novel fluoro­quinolone with a broad spectrum of anti­bacterial activity, is available as the solvated monohydro­chloride salt 7‐[(S,S)‐2‐aza‐8‐azoniabicyclo­[4.3.0]non‐8‐yl]‐1‐cyclo­propyl‐6‐fluoro‐8‐meth­oxy‐4‐oxo‐1,4‐dihydroquinoline‐3‐carboxylic acid chloride–water–methanol (2/1/1), C₂₁H₂₅FN₃O₄⁺·Cl⁻·0.5H₂O·0.5CH₃OH. The asymmetric unit contains two cations, two chloride ions, a mol­ecule of water and one methanol mol­ecule. The two cations adopt conformations that differ by an almost 180° rotation with respect to the piperidinopyrrolidine side chain. The cyclo­propyl ring and the meth­oxy group are not coplanar with the quinoline ring system. The carboxylic acid function, the protonated terminal piperidyl N atom, the water mol­ecule, the chloride ion and the methanol mol­ecule participate in O—H⋯O, O—H⋯Cl, N—H⋯O and N—H⋯Cl hydrogen bonding, linking the mol­ecules into extended two‐dimensional networks.     

Inter­actions of thia­mine with polymeric halogenocadmate anions in the organic–inorganic hybrid compound (thia­minium)[Cd3Br4.4Cl3.6]

The structure of poly[3‐[(4‐amino‐2‐methylpyrimidin‐1‐ium‐5‐yl)meth­yl]‐5‐(2‐hydroxy­ethyl)‐4‐methyl­thia­zolium octa‐μ‐bromo/chloro­(4.4/3.6)‐tricadmate(II)], {(C₁₂H₁₈N₄OS)[Cd₃ Br_4.41Cl_3.59]}_n consists of hydrogen‐bonded thia­mine mol­ecules and polymeric cadmium bromide/chloride anions in an organic–inorganic hybrid fashion. The one‐dimensional anion ribbons are formed by edge‐sharing octa­hedra and vertex‐sharing tetra­hedra. Thia­mine mol­ecules adopting the S conformation are linked to anions via three types of inter­actions, namely an N(amino)—H⋯anion⋯thia­zolium bridging inter­action, an N(pyrimidine)—H⋯anion hydrogen bond and an O(hydr­oxy)—H⋯anion hydrogen bond.     

Thia­mine tetra­phenyl­borate monohydrate: a two‐dimensional hydrogen‐bonded network with (4,4)‐topology

The title compound, 3‐[(4‐amino‐2‐methyl­pyrimidin‐5‐yl)­meth­yl]‐5‐(2‐hydroxy­eth­yl)‐4‐methyl­thia­zolium tetra­phenyl­borate monohydrate, C₁₂H₁₇N₄OS⁺·C₂₄H₂₀B⁻·H₂O, is a salt in which the thiamine cations are linked by hydrogen bonds into a two‐dimensional network having (4,4)‐topology. The stacked sheets form channels, which are occupied by the anions; the cations and anions are linked by C—H⋯π(arene) hydrogen bonds.     

Two germatranes with bulky substituents

In 1‐adamantyl‐2,8,9‐trioxa‐5‐aza‐1‐germabicyclo­[3.3.3]undecane or 1‐adamantylgermatrane, [Ge(C₁₀H₁₅)(C₆H₁₂NO₃)], (I), and (2,8,9‐trioxa‐5‐aza‐1‐germabicyclo­[3.3.3]undecan‐1‐yl)methyl N‐cyclo­hexyl­carbamate or [(germatran‐1‐yl)meth­yl] N‐cyclo­hexyl­carbamate, [Ge(C₆H₁₂NO₃)(C₈H₁₄NO₂)], (II), the Ge atoms are characterized by trigonal–bypiramidal configurations. The Ge⋯N distances [2.266 (3) and 2.206 (3) Å in (I) and (II), respectively] are among the longest observed in germatranes. The significant distortion of the apical N—Ge—C angle in (II) is caused by crystal packing effects.     

Cone and 1,3‐alternate conformers of 1,3‐bis­(ethoxy­carbonyl­methoxy)‐2,4‐di­hydroxy­calix­[4]­arene and 1,2,3,4‐tetrakis­(ethoxy­carbonyl­methoxy)­calix­[4]­arene

The two title ethoxy­carbonyl­methoxy derivatives of calix­[4]­arene, namely diethyl 2,4‐di­hydroxy­calix­[4]­arene‐1,3‐diyldi(oxy­ace­tate), C₃₆H₃₆O₈, (I), and tetraethyl ­calix­[4]­arene‐1,2,3,4‐tetra­yltetra­(oxy­acetate), C₄₄H₄₈O₁₂, (II), form two different conformations, viz. a cone in (I), where intramol­ecular hydrogen bonds are formed through OH groups in a partially substituted calix­[4]­arene, and a 1,3‐alternate form of a completely substituted calix­[4]­arene in (II). A unique three‐dimensional array of mol­ecules exists in (II), with the channels extended along the entire crystal.     

Chalcone epoxide inter­mediates in the syntheses of lignin‐related phenyl­coumarans

Compounds (2R*,3S*)‐1‐(3,4‐dimethoxy­phen­yl)‐3‐{3‐meth­oxy‐2‐[(2R*)‐tetra­hydro­pyran‐2‐yl­oxy]phen­yl}‐2,3‐ep­oxy‐1‐propanone, C₂₃H₂₆O₇, (I), and trans‐1‐(3,4‐dimethoxy­phen­yl)‐3‐[3‐meth­oxy‐2‐(methoxy­methoxy)­phen­yl]‐2,3‐ep­oxy‐1‐propanone, C₂₀H₂₂O₇, (II), were obtained on epoxidation of chalcones. The stereochemistries of (I) and (II) were elucidated. In both compounds, the substituents on the oxirane ring are trans‐oriented. Compound (I) was obtained together with a diastereometric form that differs from (I) with respect to the configuration of the asymmetric C atom in the tetra­hydro­pyran group. The geometries of the substituted oxirane rings of (I) and (II) are very similar. The hydrogen‐bonding patterns, mediated via weak C—H⋯O inter­actions, differ considerably. The crystal structures of (I) and (II) are compared with those of related chalcone epoxides. The conversion of (I) and (II) into lignin‐related phenyl­coumarans is discussed.     

Trifluoro­meth­yl derivatives of penta­cyclo­[5.4.0.02,6.03,10.05,9]undeca­ne

Three cage‐like polycyclic compounds, viz.exo‐8‐(trifluoro­meth­yl)­penta­cyclo­[5.4.0.0^2,6.0^3,10.0^5,9]undecan‐endo‐8‐ol, C₁₂H₁₃F₃O, 5‐(trifluoro­meth­yl)‐4‐oxahexa­cyclo­[5.4.1.0^2,6.0^3,10.0^5,9.0^8,11]­dodecan‐3‐ol, C₁₂H₁₁F₃O₂, and N‐[exo‐11‐(trifluoro­meth­yl)‐endo‐11‐(trimethyl­sil­yl­oxy)­penta­cyclo­[5.4.0.0^2,6.0^3,10.0^5,9]undecan‐8‐yl­idene]aniline meth­anol solvate, C₂₁H₂₄F₃NOSi·CH₄O, were obtained from the corresponding oxo derivatives by nucleophilic trifluoro­methyl­ation with (tri­fluorometh­yl)trimethyl­silane in 1,2‐dimethoxy­ethane solution in the presence of CsF. The crystal structures show that the addition of trifluoro­methanide occurs exclusively from the exo face of the polycyclic ketones. Further examination of the crystal structures, together with that of the starting penta­cyclo­[5.4.0.0^2,6.0^3,10.0^5,9]undecane‐8,11‐dione, C₁₁H₁₀O₂, showed that increasing substitution at the 8‐ and/or 11‐positions in the cage mol­ecules increases the non‐bonded intra­molecular C·C distances at the mouth of the cage and changes the puckering of the five‐membered rings involving the 8‐ and 11‐positions from an envelope towards a distorted half‐chair conformation. Inter­molecular co‐operative O—H·O hydrogen bonds in the endo‐8‐ol compound link the mol­ecules into tetra­mers.     

Disappearance of intramolecular stacking due to one‐atom movement or increment of a `propyl­ene linker' in pyrazolo­[3,4‐d]­pyrimidine‐based ­flexible models

In the crystal structures of 4,6‐di­methyl­thio‐1‐[3‐(4,6‐di­methyl­thio‐2H‐pyra­zolo­[3,4‐d]­py­rimi­din‐2‐yl)­propyl]‐1H‐py­ra­­zolo­[3,4‐d]­py­rimi­dine, C₁₇H₂₀N₈S₄, and 1‐[4‐(4‐meth­oxy‐6‐methyl­thio‐1H‐pyra­zolo­[3,4‐d]py­rimi­din‐1‐yl)­butyl]‐5‐meth­yl‐6‐methyl­thio‐4,5‐di­hydro‐1H‐pyra­zolo­[3,4‐d]py­rimi­din‐4‐one, C₁₈H₂₂N₈O₂S₂, only intermolecular stacking due to aromatic π–π interactions between pyrazolo­[3,4‐d]­pyrimidinerings is present.     

3,3a‐Dihydrocyclo­penta­[b]­chromen‐1(2H)‐ones from the reaction of salicylaldehyde and 2‐cyclo­penten‐1‐one

The two title chromene compounds, 3,3a‐dihydrocyclo­penta­[b]chromen‐1(2H)‐one, C₁₆H₁₂O₂, (I), and 2‐(2‐hydroxy­benzyl­idene)‐3,3a‐dihydrocyclo­penta­[b]chromen‐1(2H)‐one, C₁₉H₁₄O₃, (II), have been determined in the monoclinic space group P2₁/n. Compound (I) is mainly stabilized by C—H⋯π inter­actions. Compound (II) is linked into infinite one‐dimensional chains with a C(3) motif via inter­molecular O—H⋯O hydrogen bonds. The inter­molecular C—H⋯π and π–­π inter­actions also play key roles in stabilizing the crystal packing. Two intra­molecular C—H⋯O hydrogen bonds with S(5) motifs were detected in (II).     

Layered structures in proton‐transfer compounds of 5‐sulfosalicylic acid with the aromatic polyamines 2,6‐diamino­pyridine and 1,4‐phenyl­ene­diamine

The crystal structures of two proton‐transfer compounds of 3‐carb­oxy‐4‐hydroxy­benzene­sulfonic acid (5‐sulfosalicylic acid) with the aromatic polyamines 2,6‐diamino­pyridine [namely 2,6‐diamino­pyridinium 3‐carb­oxy‐4‐hydroxy­benzene­sulfonate monohydrate, C₅H₈N₃⁺·C₇H₅O₆S⁻·H₂O, (I)] and 1,4‐phenyl­ene­diamine [namely 1,4‐phenyl­ene­diaminium 3‐carboxyl­ato‐4‐hydroxy­benzene­sulfonate, C₆H₁₀N₂²⁺·C₇H₄O₆S²⁻, (II)] have been determined. Both compounds feature extensively hydrogen‐bonded three‐dimensional layered polymer structures having significant inter­layer π–π inter­actions between the cation and anion species. In (I), the pyridine N atom of the Lewis base is protonated and forms a direct hydrogen‐bonding inter­action with the water mol­ecule, which together with the two amine groups of the cation and the carboxylic acid group of the anion also give additional inter­actions with O‐atom acceptors of the sulfonate group. In (II), a dianionic species results from deprotonation of both the sulfonic and the carboxylic acid groups, and all available O‐atom acceptors inter­act with all dication donors, which lie about inversion centres.     

Bis(acesulfamato‐κ2N3,O4)bis­(2‐amino­pyrimidine‐κN1)copper(II)

In the crystal structure of the title compound, bis­(2‐amino­pyrimidine‐κN¹)bis­[6‐meth­yl‐1,2,3‐oxathia­zin‐4(3H)‐one 2,2‐dioxide(1−)‐κ²N³,O⁴]copper(II), [Cu(C₄H₄NO₄S)₂(C₄H₅N₃)₂], the first mixed‐ligand complex of acesulfame, the Cu^II centre resides on a centre of symmetry and has an octa­hedral geometry that is distorted both by the presence of four‐membered chelate rings and by the Jahn–Teller effect. The equatorial plane is formed by the N atoms of two amino­pyrimidine (ampym) ligands and by the weakly basic carbonyl O atoms of the acesulfamate ligands, while the more basic deprotonated N atoms of these ligands are in the elongated axial positions with a strong misdirected valence. The crystal is stabilized by pyrimidine ring stacking and by inter­molecular hydrogen bonding involving the NH₂ moiety of the ampym ligand and the carbon­yl O atom of the acesulfamate moiety.     

New palladium complexes with phosphino‐ and phosphinitopyridine ligands

Three new palladium complexes containing a difunctional P,N‐chelate, namely tris­(chloro­{[1‐methyl‐1‐(6‐methyl‐2‐pyridyl)ethoxy]diphenylphospine‐κ²N,P}methyl­palladium(II)chloro­form solvate, 3[Pd(CH₃)Cl(C₂₁H₂₂NOP)]·CHCl₃, (III), dichloro­[2‐(2,6‐dimethyl­phen­yl)‐6‐(diphenyl­phosphinometh­yl)­pyridine‐κ²N,P]palladium(II), [PdCl₂(C₂₆H₂₄NP)], (IV), and chloro­[2‐(2,6‐dimethyl­phen­yl)‐6‐(diphenyl­phos­phino­meth­yl)pyridine‐κ²N,P]methyl­palladium(II), [Pd(CH₃)Cl(C₂₆H₂₄NP)], (V), are reported. Geometric data and the conformations of the ligands around the metal centers, as well as slight distortions of the Pd coordination environments from idealized square‐planar geometry, are discussed and compared with the situations in related compounds. Non‐conventional hydrogen‐bond inter­actions (C—H⋯Cl) have been found in all three complexes. Compound (III) is the first six‐membered chloro–meth­yl–phosphinite P,N‐type Pd^II complex to be structurally characterized.     

Hydro­gen bonding in proton‐transfer compounds of 5‐sulfosalicylic acid with bicyclic heteroaromatic Lewis bases

The crystal structures of quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate trihydrate, C₉H₈N⁺·C₇H₅O₆S⁻·3H₂O, (I), 8‐hydroxy­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate monohydrate, C₉H₈NO⁺·C₇H₅O₆S⁻·H₂O, (II), 8‐amino­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate dihydrate, C₉H₉N₂⁺·C₇H₅O₆S⁻·2H₂O, (III), and 2‐carboxy­quinolinium 3‐carboxy‐4‐hydroxy­benzene­sulfonate quinolinium‐2‐carboxylate, C₁₀H₈NO₂⁺·C₇H₅O₆S⁻·C₁₀H₇NO₂, (IV), four proton‐transfer compounds of 5‐sulfosalicylic acid with bicyclic heteroaromatic Lewis bases, reveal in each the presence of variously hydrogen‐bonded polymers. In only one of these compounds, viz. (II), is the protonated quinolinium group involved in a direct primary N⁺—H⋯O(sulfonate) hydrogen‐bonding interaction, while in the other hydrates, viz. (I) and (III), the water mol­ecules participate in the primary intermediate interaction. The quinaldic acid (quinoline‐2‐carboxylic acid) adduct, (IV), exhibits cation–cation and anion–adduct hydrogen bonding but no direct formal heteromolecular interaction other than a number of weak cation–anion and cation–adduct π–π stacking associations. In all other compounds, secondary interactions give rise to network polymer structures.     

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.     

A chiral furocoumarin

The furocoumarin 1,2‐di­hydro‐2‐(1,2‐di­hydroxy­prop‐2‐yl)‐8H‐furo­[2,3‐h]­benzo­pyran‐8‐one crystallizes from methanol–water as the monohydrate C₁₄H₁₄O₅·H₂O. Both chiral centers have the S configuration. Both OH groups and both H atoms of the water mol­ecule form intermolecular hydrogen bonds with O?O distances in the range 2.7686 (18)–2.8717 (18) Å.     

Hydrogen bonding in 1:1 proton‐transfer compounds of 5‐sulfosalicylic acid with 4‐X‐substituted anilines (X = F,Cl or Br)

The crystal structures of three proton‐transfer compounds of 5‐sulfosalicylic acid (3‐carboxy‐4‐hydroxy­benzene­sulfonic acid) with 4‐X‐substituted anilines (X = F, Cl and Br), namely 4‐fluoro­anilinium 5‐sulfosalicylate (3‐carboxy‐4‐hydroxybenzenesulfonate) monohydrate, C₆H₇FN⁺·C₇H₅O₆S⁻·H₂O, (I), 4‐chloro­anilinium 5‐sulfosalicylate hemihydrate, C₆H₇ClN⁺·C₇H₅O₆S⁻·0.5H₂O, (II), and 4‐bromo­anilinium 5‐sulfosalicylate monohydrate, C₆H₇BrN⁺·C₇H₅O₆S⁻·H₂O, (III), have been determined. The asymmetric unit in (II) contains two formula units. All three compounds have three‐dimensional hydrogen‐bonded polymeric structures in which both the water molecule and the carboxylic acid group are involved in structure extension. With both (II) and (III), which are structurally similar, the common cyclic (8) dimeric carboxylic acid association is present, whereas in (I), an unusual cyclic (8) association involving all three hetero‐species is found.     

6‐(2‐Hydro­xy­benzoyl)‐5‐(pyrrol‐2‐yl)‐3H‐pyrrolizine

The title compound, 2‐hydroxy­phenyl 5‐(pyrrol‐2‐yl)‐3H‐pyrrolizin‐6‐yl ketone, C₁₈H₁₄N₂O₂, was isolated from the base‐catalyzed 1:2 condensation of 2‐hydroxy­aceto­phenone with pyrrole‐2‐carbaldehyde. The pyrrole N—H and hydroxy­benzoyl O—H groups are hydrogen bonded to the benzoyl O atom. The allyl­ic C=C double bond of the 3H‐pyrrolizine system is located between ring positions 1 and 2, the C atom at position 3 (adjacent to the N atom) being single bonded.     

Boc–Pro–Hyp–Gly–OBzl and Boc–Ala–Hyp–Gly–OBzl,two repeating triplets found in collagen

The protected tripeptides benzyl N‐{2‐[N‐(tert‐butoxy­carbon­yl)­prol­yl]‐4‐hydroxy­prol­yl}glycinate or Boc–Pro–Hyp–Gly–OBzl, C₂₄H₃₃N₃O₇, and benzyl N‐{2‐[N‐(tert‐butoxy­carbon­yl)­alan­yl]‐4‐hydroxy­prol­yl}glycinate or Boc–Ala–Hyp–Gly–OBzl, C₂₂H₃₁N₃O₇, are the minimum repeating triplets found in collagen. Within the crystal structure of each are two independent peptide mol­ecules with similar structures. The peptides are arranged anti­parallel to one another and inter­act through hydrogen bonds involving the main chains and the 4‐hydroxy­prolyl groups. The structures exhibit characteristics of a triple helix, but the peptides tend to assume a sheet‐like structure.     

catena‐Poly[[bis­[μ‐2,4‐dichloro‐6‐(2‐pyridyl­methyl­imino­meth­yl)phenolato]dicadmium(II)]‐di‐μ‐thiocyanato]

The title complex, [Cd₂(C₁₃H₉Cl₂N₂O)₂(NCS)₂]_n, is a novel thio­cyanate‐bridged polynuclear cadmium(II) compound. The Cd^II atom is six‐coordinated in a distorted octa­hedral configuration, with one O and two N atoms of one Schiff base mol­ecule and one terminal S atom of a bridging thio­cyanate ligand defining the equatorial plane, and one terminal N atom of another bridging thio­cyanate ligand and one O atom of another Schiff base mol­ecule occupying axial positions. Adjacent inversion‐related [2,4‐dichloro‐6‐(2‐pyridylmethyl­imino­meth­yl)phenolato]cadmium(II) moieties utilize bridging phenolate and thio­cyanate groups to form polymeric chains running along the b axis.     

The nitrate dihydrate of an aqua­dicopper(II) complex cation with guanidino­acetic acid and a novel trianionic disubstituted guanidine as ligands at 120 K

The structure of the title compound, aqua­[μ‐(N¹‐carboxylato­methyl­guanidino)­oxidoacetato](μ‐guanidino­acetic acid)­di­copper(II) nitrate dihydrate, [Cu₂(C₅H₆N₃O₅)(C₃H₇N₃O₂)(H₂O)]NO₃·2H₂O, contains two enantiomers of the di­copper(II) complex cation that comprise water, neutral zwitterionic guanidino­acetic acid and the trianion of (N¹‐carboxy­methyl­guanidino)­hydroxy­acetic acid as ligands. Extensive hydrogen bonding creates three‐dimensional connectivity but is largely confined to layers that each contain both cation enantiomers. These layers are related to one another by crystallographic symmetry and are therefore identical in composition and connectivity.