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This report presents a comprehensive investigation into the synthesis and characterization of Schiff base compounds derived from benzenesulfonamide. The synthesis process, involved the reaction between N-cycloamino-2-sulfanilamide and various substituted o-salicylaldehydes, resulted in a set of compounds that were subjected to rigorous characterization using advanced spectral techniques, including ¹H NMR, 13C NMR and FT–IR spectroscopy, and singlecrystal X-ray diffraction. Furthermore, an in-depth assessment of the synthesized compounds was conducted through Absorption, Distribution, Metabolism, Excretion and Toxicity (ADMET) analysis, in conjunction with docking studies, to elucidate their pharmacokinetic profiles and potential. Impressively, the ADMET analysis showcased encouraging drug-likeness properties of the newly synthesized Schiff bases. These computational findings were substantiated by molecular properties derived from density functional theory (DFT) calculations using the B3LYP/6-31G* method within the Jaguar Module of Schrödinger 2023-2 from Maestro (Schrodinger LLC, New York, USA). The exploration of frontier molecular orbitals (HOMO and LUMO) enabled the computation of global reactivity descriptors (GRDs), encompassing charge separation (Egap) and global softness (S). Notably, within this analysis, one Schiff base, namely, 4-bromo-2-{N-[2-(pyrrolidine-1-sulfonyl)phenyl]carboximidoyl}phenol, 20, emerged with the smallest charge separation (ΔEgap = 3.5780 eV), signifying heightened potential for biological properties. Conversely, 4-bromo-2-{N-[2- (piperidine-1-sulfonyl)phenyl]carboximidoyl}phenol, 17, exhibited the largest charge separation (ΔEgap = 4.9242 eV), implying a relatively lower propensity for biological activity. Moreover, the synthesized Schiff bases displayed remarkeable inhibition of tankyrase poly(ADP-ribose) polymerase enzymes, integral in colon cancer, surpassing the efficacy of a standard drug used for the same purpose. Additionally, their bioavailability scores aligned closely with established medications such as trifluridine and 5-fluorouracil. The exploration of molecular electrostatic potential through colour mapping delved into the electronic behaviour and reactivity tendencies intrinsic to this diverse range of molecules. [ABSTRACT FROM AUTHOR]

The negative environmental and human health challenges posed by sulfur oxides that are released upon combustion of fuel oils containing sulfur necessitate the development of methods for its removal, and hydroprocessing is the conventional technique. However, dibenzothiophene and its substituted derivatives are refractory. As such, the coordination polymers (CPs): [Co(tmdp)4Cl2]n1 and [Zn(tpa)2(tmdp)2·(H2O)2]n2, where tmdp is trimethylenedipyridine and tpa is terephthalic acid, were synthesized for application in adsorptive separation to selectively remove the refractory compounds. Spectroscopy techniques (UV-vis and FT-IR), single crystal XRD, micro-elemental analysis, TGA and SEM were used for characterization. Heat activation of both CPs was carried out to remove lattice solvent molecules before applying them in adsorption. Both CPs, showed good adsorption of dibenzothiophene (DBT) with maximum adsorption capacities of 49 mg g−1 and 44 mg g−1, respectively. The adsorption studies and theoretical studies carried out pointed to physisorption as the mechanism for adsorption of DBT in both CPs with interactions being predominantly dispersion forces between the ligands and DBT. [ABSTRACT FROM AUTHOR]

In the search for new 'sulfa drugs' with therapeutic properties, o‐nitrosulfonamides and N‐cycloamino‐o‐sulfanilamides were synthesized and characterized using techniques including 1H NMR, 13C NMR and FT–IR spectroscopy, and single‐crystal X‐ray diffraction (SC‐XRD). The calculated density functional theory (DFT)‐optimized geometry of the molecules showed similar conformations to those obtained by SC‐XRD. Molecular docking of N‐piperidinyl‐o‐sulfanilamide and N‐indolinyl‐o‐sulfanilamide supports the notion that o‐sulfanilamides are able to bind to human carbonic anhydrase II and IX inhibitors (hCA II and IX; PDB entries 4iwz and 5fl4). Hirshfeld surface analyses and DFT studies of three o‐nitrosulfonamides {1‐[(2‐nitrophenyl)sulfonyl]pyrrolidine, C10H12N2O4S, 1, 1‐[(2‐nitrophenyl)sulfonyl]piperidine, C11H14N2O4S, 2, and 1‐[(2‐nitrophenyl)sulfonyl]‐2,3‐dihydro‐1H‐indole, C14H12N2O4S, 3} and three N‐cycloamino‐o‐sulfanilamides [2‐(pyrrolidine‐1‐sulfonyl)aniline, C10H14N2O2S, 4, 2‐(piperidine‐1‐sulfonyl)aniline, C11H16N2O2S, 5, and 2‐(2,3‐dihydro‐1H‐indole‐1‐sulfonyl)aniline, C14H14N2O2S, 6] suggested that forces such as hydrogen bonding and π–π interactions hold molecules together and further showed that charge transfer could promote bioactivity and the ability to form biological interactions at the piperidinyl and phenyl moieties. [ABSTRACT FROM AUTHOR]

A novel distorted square-planar palladium(II) complex of the type [Pd(Hdz)(PPh3)Cl], where (Hdz = dithizone mono deprotonate and PPh3 = triphenylphosphine), was synthesized in dichloromethane reactions between PdCl2 and a mixture of Hdz and PPh3. The new Pd(II) complex has been identified by FT-IR, electronic spectra, DFT calculations, molar conductivity, and single-crystal X-ray diffraction. An X-ray diffraction study revealed the structure of this complex, indicating distorted square planar coordination geometry around the Pd(II) ion by N, S, P, and Cl donor atoms. XRD analysis has also shown that the Pd(II) complex contains one fivemembered ring formed by the coordination of the Hdz ligand through the nitrogen and sulfur atoms to the palladium metal center. To comprehend the strength of nucleophilic and electrophilic attack between the ligands and metal ions, the natural bond orbital (NBO) was used. Finally, density functional theory (DFT) was used to show the molecular reactivity and stability of the ligands and palladium complex. [ABSTRACT FROM AUTHOR]

The title compound, 10‐iodo‐1,2‐dihydroisoquinolino[2,1‐b][1,2,4]benzothiadiazine 12,12‐dioxide, C15H11IN2O2S (8), was synthesized via the metal‐free intramolecular N‐iodosuccinimide (NIS)‐mediated radical oxidative sp3‐C—H aminative cyclization of 2‐(2′‐aminobenzenesulfonyl)‐1,3,4‐trihydroisoquinoline, C15H16N2O2S (7). The amino adduct 7 was prepared via a two‐step reaction, starting from the condensation of 2‐nitrobenzenesulfonyl chloride (4) with 1,2,3,4‐tetrahydroisoquinoline (5), to afford 2‐(2′‐nitrobenzenesulfonyl)‐1,3,4‐trihydroisoquinoline, C15H14N2O4S (6), in 82% yield. The catalytic hydrogenation of 6 with hydrogen gas, in the presence of 10% palladium‐on‐charcoal catalyst, furnished 7. Products 6–8 were characterized by their melting points, IR and NMR (1H and 13C) spectroscopy, and single‐crystal X‐ray diffraction. The three compounds crystallized in the monoclinic space group, with 7 exhibiting classical intramolecular hydrogen bonds of 2.16 and 2.26 Å. All three crystal structures exhibit centrosymmetric pairs of intermolecular C—H...π(ring) and/or π–π stacking interactions. The docking studies of molecules 6, 7 and 8 with deoxyribonucleic acid (PDB id: 1ZEW) revealed minor‐groove binding behaviours without intercalation, with 7 presenting the most favourable global energy of the three molecules. Nonetheless, molecule 8 interacted strongly with the DNA macromolecule, with an attractive van der Waals energy of −15.53 kcal mol−1. [ABSTRACT FROM AUTHOR]

C10H18O5, monoclinic, P21/c (no. 14), a = 11.3561(7) Å, b = 11.4569(7) Å, c = 10.9762(6) Å, β = 116.087(2)°, V = 1282.58(13) Å3, Z = 4, Rgt(F) = 0.0547, wRref(F2) = 0.1677, T = 200 K. [ABSTRACT FROM AUTHOR]

C7H6BrCl, orthorhombic, Pna21 (no. 33), a = 9.4506(7) Å, b = 18.1015(10) Å, c = 4.4418(3) Å, V = 759.86(9) Å3, Z = 4, Rgt(F) = 0.0271, wRref(F2) = 0.0558, T = 200(2) K. [ABSTRACT FROM AUTHOR]

C6H5ClS, monoclinic, P21/n (no. 14), a = 5.7461(2) Å, b = 9.7601(4) Å, c = 5.7466(3) Å, β = 95.869(2)°, V = 320.59(2) Å3, Z = 2, Rgt(F) = 0.0216, wRref(F2) = 0.0545, T = 200 K. [ABSTRACT FROM AUTHOR]

C10H18O5, monoclinic, P21/c (no. 14), a = 11.3561(7) Å, b = 11.4569(7) Å, c = 10.9762(6) Å, β = 116.087(2)°, V = 1282.58(13) Å3, Z = 4, Rgt(F) = 0.0547, wRref(F2) = 0.1677, T = 200 K. [ABSTRACT FROM AUTHOR]

C8H14O5S, monoclinic, P21 (no. 4), a = 6.3783(4) Å, b = 8.2630(5) Å, c = 10.5891(7) Å, β = 90.877(2)°, V = 558.02(6) Å3, Z = 2, Rgt(F) = 0.0254, wRref(F2) = 0.0715, T = 200 K. [ABSTRACT FROM AUTHOR]

C17H30N2, tetragonal, P4 ‾ 21m (no. 113), a = 8.6755(3) Å, c = 11.1611(4) Å, V = 840.03(7) Å3, Z = 2, Rgt(F) = 0.0488, wRref(F2) = 0.1417, T = 200 K. [ABSTRACT FROM AUTHOR]

C13H8O3S, monoclinic, C2/c (no. 15), a = 9.7499(3) Å, b = 12.9758(4) Å, c = 8.2681(3) Å, β = 103.784(2)°, V = 1015.90(6) Å3, Z = 4, Rgt(F) = 0.0318, wRref(F2) = 0.0927, T = 200 K. [ABSTRACT FROM AUTHOR]

C17H30N2, tetragonal, P4 ‾ 21m (no. 113), a = 8.6755(3) Å, c = 11.1611(4) Å, V = 840.03(7) Å3, Z = 2, Rgt(F) = 0.0488, wRref(F2) = 0.1417, T = 200 K. [ABSTRACT FROM AUTHOR]

C21H18O2, triclinic, P1 (no. 2), a = 9.8213(6) Å, b = 9.9212(6) Å, c = 10.0400(6) Å, α = 65.510(2)°, β = 63.539(2)°, γ = 84.842(2)°, V = 791.59(8) Å3, Z = 2, Rgt(F) = 0.0463, wRref(F2) = 0.1101, T = 200 K. [ABSTRACT FROM AUTHOR]

C15H14O4, monoclinic, C2/c (no. 15), a = 27.1122(8) Å, b = 6.4295(2) Å, c = 14.7495(4) Å, β = 91.7070(10)°, V = 2569.96(13) Å3, Z = 8, Rgt(F) = 0.0387, wRref(F2) = 0.1091, T = 200 K. [ABSTRACT FROM AUTHOR]

C6H8N2O6, monoclinic, P21/c (no. 14), a = 7.4709(4) Å, b = 14.2051(9) Å, c = 7.3198(4) Å, β = 97.096(4)°, V = 770.86(8) Å3, Z = 4, Rgt(F) = 0.0346, wRref(F2) = 0.0946, T = 200 K. [ABSTRACT FROM AUTHOR]

C19H14ClNO2, monoclinic, P21/c (no. 14), a = 19.328(4) Å, b = 7.1086(12) Å, c = 11.627(2) Å, β = 99.417(9)°, V = 1576.0(5) Å3, Z = 4, Rgt(F) = 0.0582, wRref(F2) = 0.1615, T = 200 K. [ABSTRACT FROM AUTHOR]

C12H9NS, monoclinic, P21/n (no. 14), a = 5.0743(5) Å, b = 14.0545(13) Å, c = 13.3319(17) Å, β = 91.102(5)°, V = 950.61(18) Å3, Z = 4, Rgt(F) = 0.0322, wRref(F2) = 0.0908, T = 200 K. [ABSTRACT FROM AUTHOR]

C7H6BrNO2, orthorhombic, P212121 (no. 19), a = 4.7019(6) Å, b = 6.4700(9) Å, c = 25.283(4) Å, V = 769.14(19) Å3, Z = 4, Rgt(F) = 0.0294, wRref(F2) = 0.0671, T = 200 K. [ABSTRACT FROM AUTHOR]

C6H15Cl2N, triclinic, P1 (no. 2), a = 6.9579(4) Å, b = 8.1852(5) Å, c = 8.7912(5) Å, α = 66.606(2)°, β = 86.105(3)°, γ = 89.834(2)°, V = 458.30(5) Å3, Z = 2, Rgt(F) = 0.0226, wRref(F2) = 0.0599, T = 200 K. [ABSTRACT FROM AUTHOR]

C12H10O3Se2, triclinic, P1 (no. 2), a = 9.1794(3) Å, b = 11.5706(5) Å, c = 12.3976(5) Å, α = 85.291(2)°, β = 72.198(2)°, γ = 74.084(2)°, V = 1205.65(8) Å3, Z = 4, Rgt(F) = 0.0275, wRref(F2) = 0.0698, T = 200 K. [ABSTRACT FROM AUTHOR]

C6H4Br2FN, monoclinic, P21/c (no. 14), a = 17.0332(5) Å, b = 4.34070(10) Å, c = 21.9732(5) Å, β = 109.6910(10)°, V = 1529.61(7) Å3, Z = 8, Rgt(F) = 0.0256, wRref(F2) = 0.0518, T = 200 K. [ABSTRACT FROM AUTHOR]

C8H18ClNO2, monoclinic, P21/c (no. 14), a = 6.8110(5) Å, b = 8.8779(7) Å, c = 17.2774(16) Å, β = 97.582(4)°, V = 1035.59(15) Å3, Z = 4, Rgt(F) = 0.0484, wRref(F2) = 0.0922, T = 200 K. [ABSTRACT FROM AUTHOR]

C6H10Cl2N2O, triclinic, P1 (no. 2), a = 4.8274(4) Å, b = 8.0556(7) Å, c = 12.0648(10) Å, α = 71.237(4)°, β = 78.739(4)°, γ = 72.950(4)°, V = 422.06(6) Å3, Z = 2, Rgt(F) = 0.0225, wRref(F2) = 0.0614, T = 190 K. [ABSTRACT FROM AUTHOR]

C14H14F6N2O, orthorhombic, Pbcn (no. 60), a = 17.7552(12) Å, b = 10.7574(9) Å, c = 8.0207(7) Å, V = 1532.0(2) Å3, Z = 4, Rgt(F) = 0.0415, wRref(F2) = 0.1154, T = 200 K. [ABSTRACT FROM AUTHOR]

C32H30N8O5, orthorhombic, P212121 (no. 19), a = 9.1258(4) Å, b = 10.6225(5) Å, c = 30.1870(14) Å, V = 2926.3(2) Å3, Z = 4, Rgt(F) = 0.0367, wRref(F2) = 0.0837, T = 200 K. [ABSTRACT FROM AUTHOR]

C12H12Cl4NSb, monoclinic, P21/n (no. 14), a = 5.6693(2) Å, b = 20.2385(7) Å, c = 14.3908(5) Å, β = 100.3830(10)°, V = 1624.14(10) Å3, Z = 4, Rgt(F) = 0.0192, wRref(F2) = 0.0430, T = 200 K. [ABSTRACT FROM AUTHOR]

C9H24N2O7, monoclinic, P21/n (no. 14), a = 11.1646(7) Å, b = 6.3264(4) Å, c = 18.6926(9) Å, β = 97.5994(18)°, V = 1308.69(13) Å3, Z = 4, Rgt(F) = 0.0385, wRref(F2) = 0.1057, T = 200 K. [ABSTRACT FROM AUTHOR]

C6H8N2O6, monoclinic, P21/c (no. 14), a = 7.4709(4) Å, b = 14.2051(9) Å, c = 7.3198(4) Å, β = 97.096(4)°, V = 770.86(8) Å3, Z = 4, Rgt(F) = 0.0346, wRref(F2) = 0.0946, T = 200 K. [ABSTRACT FROM AUTHOR]

C15H14O4, monoclinic, C2/c (no. 15), a = 27.1122(8) Å, b = 6.4295(2) Å, c = 14.7495(4) Å, β = 91.7070(10)°, V = 2569.96(13) Å3, Z = 8, Rgt(F) = 0.0387, wRref(F2) = 0.1091, T = 200 K. [ABSTRACT FROM AUTHOR]

C19H14ClNO2, monoclinic, P21/c (no. 14), a = 19.328(4) Å, b = 7.1086(12) Å, c = 11.627(2) Å, β = 99.417(9)°, V = 1576.0(5) Å3, Z = 4, Rgt(F) = 0.0582, wRref(F2) = 0.1615, T = 200 K. [ABSTRACT FROM AUTHOR]

C12H10O3Se2, triclinic, P1 (no. 2), a = 9.1794(3) Å, b = 11.5706(5) Å, c = 12.3976(5) Å, α = 85.291(2)°, β = 72.198(2)°, γ = 74.084(2)°, V = 1205.65(8) Å3, Z = 4, Rgt(F) = 0.0275, wRref(F2) = 0.0698, T = 200 K. [ABSTRACT FROM AUTHOR]

C32H30N8O5, orthorhombic, P212121 (no. 19), a = 9.1258(4) Å, b = 10.6225(5) Å, c = 30.1870(14) Å, V = 2926.3(2) Å3, Z = 4, Rgt(F) = 0.0367, wRref(F2) = 0.0837, T = 200 K. [ABSTRACT FROM AUTHOR]

C8H18ClNO2, monoclinic, P21/c (no. 14), a = 6.8110(5) Å, b = 8.8779(7) Å, c = 17.2774(16) Å, β = 97.582(4)°, V = 1035.59(15) Å3, Z = 4, Rgt(F) = 0.0484, wRref(F2) = 0.0922, T = 200 K. [ABSTRACT FROM AUTHOR]

C9H24N2O7, monoclinic, P21/n (no. 14), a = 11.1646(7) Å, b = 6.3264(4) Å, c = 18.6926(9) Å, β = 97.5994(18)°, V = 1308.69(13) Å3, Z = 4, Rgt(F) = 0.0385, wRref(F2) = 0.1057, T = 200 K. [ABSTRACT FROM AUTHOR]

A base-catalyzed conversion of aldehydes to benzimidazoles has been achieved. The compounds have been characterized by IR, NMR, micoranalysis, and GC-MS. The reaction for the formation of benzimidazoles has been monitored with 1H NMR and IR. The crystal structures of two derivatives, 2-(2- chlorophenyl)-1H-benzimidazole and 2-(1H-benzimidazol-2-yl)-4-nitrophenol, are presented. A study of the DPPH scavenging activity of these compounds showed that 2-(1H-benzimidazol-2-yl)phenol (2), 2-p-tolyl-1Hbenzimidazole (3) and 2-(4-methoxyphenyl)-1H-benzimidazole (7) gave IC50 values 1974, 773 and 800 μM. [ABSTRACT FROM AUTHOR]

Organotin(IV) dithiocarbamate complexes, RSnClL 2 and R 2 SnL 2 (R = Me, Bu, Ph, and L = N -ethyl- N -phenyldithiocarbamate), have been synthesized by the reaction of mono- and disubstituted organotin(IV) with ammonium dithiocarbamate. The complexes were characterized by elemental analyses, and spectroscopic techniques ( 1 H, 13 C NMR and FTIR). The structures of Me 2 SnL 2 and Bu 2 SnL 2 were further established by single crystal X-ray diffraction technique. The crystal structure analysis showed that both complexes (Me 2 SnL 2 and Bu 2 SnL 2 ) exist as monomers. One of the dithiocarbamate ligands formed a chelate, while the other dithiocarbamate bonded to the central tin atom through one of the sulfur atoms and the second sulfur atom existed as a pendant to form distorted trigonal bipyramidal geometry. The thermal stability of all the complexes was studied using simultaneous thermogravimetry (TG) and differential scanning calorimetry (DSC). The TG-DSC results showed that Me 2 SnL 2 , BuSnClL 2 , Bu 2 SnL 2 , and PhSnClL 2 displayed similar decomposition pathway via isothiocyanate intermediate, while MeSnClL 2 and Ph 2 SnL 2 showed decomposition pathways different from the rest of the complexes. All the complexes resulted in SnS as the final product of the thermal decomposition process. [ABSTRACT FROM AUTHOR]

The synthesis, characterization and crystal structures of three chloroform solvated adducts of cadmium with mixed ligands of N -alkyl- N -phenyldithiocarbamate and pyridine, 2,2-bipyridine and 1, 10 phenanthroline represented as [CdL 1 L 2 (py) 2 ]·CHCl 3 (1) , [CdL 1 L 2 bpy]∙CHCl 3 (2) , and [CdL 1 L 2 phen]∙CHCl 3 (3) (L I = N -methyl- N -phenyldithiocarbamate, L 2 = N -ethyl- N -phenyldithiocarbamate, py = pyridine, bpy = 2,2-bipyridine and phen = 1,10-phenanthroline) respectively are reported. Complex 1, which crystallized in the monoclinic space group P-1, is a centrosymmetric dimeric structure where each Cd center is bonded to two monodentate pyridine, a bidentate terminal dithiocarbamate, and another bidentate bridging dithiocarbamate to form a four-membered ring. Complex 2 crystallized in the monoclinic space group P 2 1 / c , with four discrete monomeric molecules in the asymmetric unit. The structure presents a cadmium atom coordinated by two sulphur atoms of a dithiocarbamate ligand and two nitrogen atoms of the 2,2′-bipyridine to form a CdS 4 N 2 fragment, thus giving the structure around the Cd atom a distorted trigonal prism geometry. Complex 3 contains two discrete monomeric molecules of (phenanthroline) ( N , N –methyl phenyl– N , N –ethyl phenyl dithiocarbamato)cadmium (II) per unit cell, and the complex crystallized in the triclinic space group P-1. The structure showed that the Cd atom is bonded to two bidentate dithiocarbamate ligands and to one bidentate phenanthroline ligand in a distorted trigonal prism geometry. All the compounds resulted in CdS as residue upon thermal decomposition process conducted under inert atmosphere. [ABSTRACT FROM AUTHOR]

The title compound, [Cd2(C7H10NS2)4], is a neutral dinuclear cadmium(II) complex bearing four bis N,N-diallyldithiocarbamate ligands coordinating to two CdII cations. In each of the monomeric subunits, there are four S atoms of two dithiocarbamate ligands [Cd--S = 2.5558 (3), 2.8016 (3), 2.6050 (3) and 2.5709 (3) Å ] that coordinate to one CdII atom in a bidentate mode. The dimers are located over an inversion centre bridged by two additional bridging Cd--S bonds [2.6021 (3) Å ], leading to a substantial distortion of the geometry of the monomeric subunit from the expected square-planar geometry. The fivecoordinate environment around each of the CdII ions in the dimer is best described as substantially tetragonally distorted square pyramidal. The dithiocarbamate groups are themselves planar and are also coplanar with the CdII ions. The negative charge on these groups is delocalized by resonance across the S atoms bound to the CdII cation. This delocalization of the π electrons in the dithiocarbamate groups also extends to the C--N bonds as they reveal significant double bond character [C--N = 1.3213 (16) and 1.3333 (15) Å ]. [ABSTRACT FROM AUTHOR]

(C20H20P)2 [CuBr4], monoclinic, P21/n, a=24.6469(9) Å, b=12.4301(5) Å, c=25.5369(9) Å, b=91.016(2)°, V=7822.3(5) ų, Z=8, Rgt(F)=0.0733, wRref(F²)=0.1806, T=200. [ABSTRACT FROM AUTHOR]

(C20H20P)2 [CuBr4], monoclinic, P21/n, a=24.6469(9) Å, b=12.4301(5) Å, c=25.5369(9) Å, b=91.016(2)°, V=7822.3(5) ų, Z=8, Rgt(F)=0.0733, wRref(F²)=0.1806, T=200. [ABSTRACT FROM AUTHOR]

The reaction of benzoyl isothiocyanate with l -serine, l -proline, d -methionine and l -alanine gave 2-[(benzoylcarbamothioyl)amino]-3-hydroxypropanoic acid ( I ), 1-(benzoylcarbamothioyl)pyrrolidine-2-carboxylic acid ( II ), 2-[(benzoylcarbamothioyl)amino]-4-(methylsulfanyl)butanoic acid ( III ) and 2-[(benzoylcarbamothioyl)amino]propanoic acid ( IV ), respectively. The compounds have been characterized by IR, NMR, microanalyses and mass spectrometry. The crystal structures of all the compounds have also been discussed. Compound II showed rotamers in solution. DFT calculations of the frontier orbitals of the compounds have been carried out to ascertain the groups that contribute to the HOMO and LUMO, and to study their contribution to the reactivity of these compounds. The calculations indicated that the carboxylic acid group in these compounds is unreactive hence making the conversion to benzimidazoles via cyclization on the carboxylic acids impractical. This has been further confirmed by the reaction of compounds I – IV , respectively, with o -phenylene diamine which was unsuccessful but gave compound V . [ABSTRACT FROM AUTHOR]

Copyright of Zeitschrift für Kristallographie / New Crystal Structures is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Zeitschrift für Kristallographie / New Crystal Structures is the property of De Gruyter and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

C6H11BrO2, monoclinic, P21/n (no. 14), a = 10.6730(14) Å, b = 5.2781(6) Å, c = 14.7781(18) Å, β = 109.610(4)°, V = 784.21(17) Å3, Z = 4, Rgt(F) = 0.0225, wRref(F2) = 0.0564, T = 200(2) K. [ABSTRACT FROM AUTHOR]

C6H11BrO2, monoclinic, P21/n (no. 14), a = 10.6730(14) Å, b = 5.2781(6) Å, c = 14.7781(18) Å, β = 109.610(4)°, V = 784.21(17) Å3, Z = 4, Rgt(F) = 0.0225, wRref(F2) = 0.0564, T = 200(2) K. [ABSTRACT FROM AUTHOR]

Two sulfanylidene-1,2,3,4-tetrahydropyrimidine derivatives have been synthesized using acid-catalysed cyclocondensation reactions between thiourea, ethyl 3-oxobutanoate and substituted benzaldehydes. In each of ethyl (4 RS)-4-(4-benzyloxyphenyl)-6-methyl-2-sulfanylidene-1,2,3,4-tetrahydropyrimidine-5-carboxylate, C21H22N2O3S, (I), where Z′ = 2, and ethyl (4 RS)-4-(4-methoxyphenyl)-6-methyl-2-sulfanylidene-1,2,3,4-tetrahydropyrimidine-5-carboxylate 0.105-hydrate, C15H18N2O3S·0.105H2O, (II), the reduced pyrimidine ring adopts a conformation intermediate between the boat, screw-boat and twist-boat forms. In (I) and (II), a combination of N-H...O and N-H...S hydrogen bonds links the organic molecules into ribbons containing alternating R22(8) and R44(20) rings. In (I), the ribbon contains three types of ring, viz. two different R22(8) rings which are both centrosymmetric and R44(20) rings which are not centrosymmetric. In (II), the ribbon contains two types of ring, both of which are centrosymmetric. In compound (II), the ribbons enclose continuous channels which run along the twofold rotation axes in the space group C2/ c, and the partial-occupancy water molecules lie within these channels. Structural comparisons are made with a number of related compounds. [ABSTRACT FROM AUTHOR]

The structures of a chalcone and of its cyclocondensation product with guanidine are reported. In (2 E)-3-(6-methoxynaphthalen-2-yl)-1-(pyridin-3-yl)prop-2-en-1-one, C19H15NO2, (I), the planes of the pyridine and naphthalene units make dihedral angles with that of the central spacer unit of 23.61 (13) and 23.57 (15)°, respectively, and a dihedral angle of 47.24 (9)° with each other. The molecules of (I) are linked into sheets by a combination of C-H...O and C-H...π(arene) hydrogen bonds. In the cyclocondensation product (4 RS)-2-amino-4-(6-methoxynaphthalen-2-yl)-6-(pyridin-3-yl)-3,4-dihydropyrimidine monohydrate, C20H18N4O·H2O, (II), the dihydropyrimidine ring adopts a conformation best described as a shallow boat. The molecular components are linked by two N-H...O hydrogen bonds, two O-H...N hydrogen bonds and one N-H...N hydrogen bond to form complex sheets, with the methoxynaphthalene interdigitated between inversion-related pairs of sheets. [ABSTRACT FROM AUTHOR]

Four imidazo[2,1- b][1,3,4]thiadiazoles containing a simply-substituted 6-aryl group have been synthesized by reaction of 2-amino-1,3,4-thiadiazoles with bromoacetylarenes using microwave irradiation and brief reaction times. 6-(2-Chlorophenyl)imidazo[2,1- b][1,3,4]thiadiazole, C10H6ClN3S, (I), 6-(2-chlorophenyl)-2-methylimidazo[2,1- b][1,3,4]thiadiazole, C11H8ClN3S, (II), 6-(3,4-dichlorophenyl)imidazo[2,1- b][1,3,4]thiadiazole, C10H5Cl2N3S, (III), and 6-(4-fluoro-3-methoxyphenyl)-2-methylimidazo[2,1- b][1,3,4]thiadiazole, C12H10FN3OS, (IV), crystallize with Z′ values of 2, 1, 1 and 2 respectively. The molecular skeletons are all nearly planar and the dihedral angles between the imidazole and aryl rings are 1.51 (8) and 7.28 (8)° in (I), 9.65 (7)° in (II), 10.44 (8)° in (III), and 1.05 (8) and 7.21 (8)° in (IV). The molecules in (I) are linked by three independent C-H...N hydrogen bonds to form ribbons containing alternating R22(8) and R44(18) rings, and these ribbons are linked into a three-dimensional array by three independent π-stacking interactions. Both (II) and (III) contain centrosymmetric dimers formed by π-stacking interactions but hydrogen bonds are absent, and the molecules of (IV) are linked into centrosymmetric R22(8) dimers by C-H...N hydrogen bonds. Comparisons are made with a number of related compounds. [ABSTRACT FROM AUTHOR]