Structures of 1,2,3,4-tetrahydro-6H-pyrimido[2,1-b]-quinazolin-6-one and its hydrochloride

C₁₁H₁₁N₃O, m.p. 243°C, P2/n,Z=4,a=5.843(2),b=14.241(3),c=11.102(1) Å, =93.30(2)°,R=0.046; C₁₁H₁₁N₃O·HCl·H₂O, Pca2₁,Z=8,a=18.640(2),b=8.894(2),c=14.404(2)Å,R=0.062. The molecules of the free base are in 1H-tautomeric form. N(1)-H...N(11) hydrogen bonds join molecules of the free base into dimers, which enable tautomeric rearrangement (not observed in this study) also in the solid state without any changes in molecular packing. The quinazoline system deviates slightly from planarity and benzene electrons are partially localized at C(7)–C(8) and C(9)–C(10) bonds as seen from their lengths of about 1.375 Å, while other bonds in the benzene ring are at least 0.02 Å longer.     

X-ray structure of 5-phenyl-1,3,4-oxathiazol-2-one

The X-ray crystal structure of 5-phenyl-1,3,4-oxathiazol-2-one has been determined. Colorless, regular plate shaped crystals of C₈H₅O₂NS crystallize in the monoclinic space group P2₁/n (#14) with cell dimensionsa=11·161(8),b=7·1470(20),c=19·864(15) Å and =99·77(4)°;V=1561·5(17) ų andZ=8.1725 unique reflections withl _net>2.5(l) on refinement afforded values ofR=0.054 andR _w=0.049.     

Crystal structures of two local anesthetics: Dibucaine·HCl·H2O and Dimethisoquin·HCl·H2O

The crystal structures of the tertiary amine local anesthetics dibucaine hydrochloride monohydrate (C₂₀H₂₉N₃O₂·HCl·H₂O) and dimethisoquin hydrochloride monohydrate (C₁₇H₂₄N₂O·HCl·H₂O) have been determined. Dibucaine forms crystals inP2₁/c witha=10.669(3),b = 35.981(5),c= 11.417(2) Å,= 89.654(3) ° andZ= 8. Dimethisoquin crystallizes in the space groupP¯1 witha = 5.338(6),b=7.579(8),c= 22.336(24) Å,a = 85.513(1), = 87.447(1), =84.863(1) °, andZ=2. Intensity data were collected with an automatic diffractometer, using CuK for dibucaine and MoK for dimethisoquin. The structures were solved using direct methods and refined by full-matrix least-squares procedures to final values ofR= 12.8% for dibucaine andR = 8.8% for dimethisoquin. The structures of both local anesthetics feature planar fused ring systems and extended side chains, one of which contains the tertiary amine that forms hydrogen bonds with other local anesthetic molecules and the chlorine and solvent atoms. The possible sites of action of the anesthetics in the cell membrane are discussed on the basis of these structures.     

Crystal structure of two lipophilic antifolates: 2,4-diamino-5-(n-hexyl)-6-methylpyrimidine and 2,4-diamino-5-(n-heptyl)-6-methylpyrimidine ethanesulfonate

The 5-hexyl (I) and the 5-heptyl (II) analogs of 2,4-diamino-6-methylpyrimidine both crystallize in the space groupP2₁/c withZ=4. Unit cell parameters of I are C₁₁H₂₀N₄·H₂O,a=17.204(3),b=4.609(9),c=16.765(2)Å,= 91.53(2)°; those of II are C₁₂H₂₃N₄ ⁺·C₂H₅SO₃ ^–,a=12.489(1),b=16.702(2),c=8.9558(7)Å,=99.208(8)°. The molecular packing of I contains one water, while II forms a salt with ethanesulfonic acid. The alkyl chain of I adopts an alltrans conformation; in contrast, II has onegauche orientation between carbons 2 and 3 of heptyl. These are the first structural data on two alkyl lipophilic antifolates with antineoplastic activity.     

Hydrogen bonding in 2-hydroxy((di)thio)benzoates. I. X-ray structures of 2,6-dimethylpiperidinium salts

X-ray structural data are reported for 2,6-dimethyl-piperidinium-2-hydroxybenzoate (C₁₄H₂₁NO₃, orthorhombic,P2₁2₁,2₁, (19);a=7.983(1)Å,b=12.680(2)Å,c=13.838(2)Å;Z=4;R=0.042) and for two polymorphs of 2,6-dimethylpiperidinium-2-hydroxythiobenzoate (C₁₄H₂₁NO₂S), an-form (monoclinic,P2₁/n (14);a=8.005(4)Å,b=22.150(2)Å,c=8.672(4)Å,=101.91(6)°;Z=4;R=0.059) with an intramolecular O-HS hydrogen bond, and a-form (orthorhombic,P2₁2₁2₁ (19);a=8.188(1)Å,b=14.781(2)Å,c=24.163(4)Å;Z=8;R=0.15) with an intramolecular O-HO hydrogen bond. The intra-and intermolecular hydrogen bond patterns are discussed, including the literature data of 2,6-dimethylpiperidinium-2-hydroxydithiobenzoate.     

Synthesis and X-ray structures of [H3O+·18-crown-6] n [MCl 4 n− ]; (M=Fe,n=1;M=Co,n=2); compounds which form liquid clathrates with aromatic solutions

The title compounds, [H₃O⁺·18-crown-6][FeCl ₄ ^– ] (1), and [H₃O⁺·18-crown-6]₂[CoCl ₄ ^2– ] (2), were prepared by air oxidation of Fe(CO)₅ for1, and Co₂(CO)₈ for2, in the presence of 18-crown-6, H₂O and HCl(g) in toluene. Liquid clathrates formed immediately for both species:1·4.3 C₇H₈ and2·3.7 C₇H₈.1 crystallizes in the orthorhombic space group P2₁ma witha=10.357(1),b=11.824(1),c=8.961(1) Å, andD _c=1.46 g cm^–3 forZ=2. Refinement based on 935 observed reflections led to a finalR value of 0.089.2 crystallizes in the monoclinic space group C2/c witha=16.225(1),b=11.522(1),c=20.136(1)Å, =97.75(2)^o, andD _c=1.37 g cm^–3 forZ=4. Refinement based on 1322 observed reflections led to a finalR value of 0.11.     

Diastereoisomers of a prednisolone derivative

The crystal and molecular structures of two synthetic corticosteroid diastereoisomers were determined by X-ray diffraction methods. (22R)-21-acetoxy-16,17-furfurylidenedioxy-11-hydroxy-pregna-1,4-diene-3,20-dione, C₂₈H₃₂O₈, crystallized in the orthorhombic system, space group P2₁2₁2₁,a=6.346(1),b=14.106(2),c=27.901(3) Å, andZ=4. (22S)-21-acetoxy-16, 17-furfurylidenedioxy-11-hydroxy-5 pregna-1,4-diene-3,20-dione ethanolate, C₂₈H₃₂O₈ ·C₂H₅OH, crystallized in the monoclinic system, space group C2,a=20.382(5),b=8.331(1),c=17.346(4)Å, =103.43(2)°, andZ=4. A change of configuration at the C(22) chirality center has influence on the remote parts of the molecules. The long-range effects appear in the ability to form intermolecular hydrogen bonds by different atoms and consequently in the solvation of the (S) diastereoisomer.     

Molecular structure and hydrogen bonding of 4-dimethylaminopyridinioacetate in its crystalline dihydrate and hydrochloride trihydrate,L·2H2O and [L2H]Cl·3H2O (L=p-Me2NC5H4N+CH2CO2 −)

The crystalline dihydrate and hydrochloride trihydrate of a new betaine, namely, L·2H₂O (1) and [L₂H]Cl·3H₂O(2) (L=p-Me₂NC₅H₄N⁺CH₂CO₂), have been synthesized and characterized by X-ray crystallography. Molecule L in compound1 [space groupPbcn, witha=15.732(3),b=7.894(2),c=18.304(4) Å, andZ=8] possesses approximateC _s symmetry. The formation of hydrogen bonds by water molecules bridging neighboring carboxy oxygen atoms leads to an infinite two-dimensional network composed of a packing of two different kinds of 12-membered rings. In compound2 [space group PT witha=7.341(2),b=9.543(2),c=17.010(4) Å, =82.43(2)°, =80.34(2)°, =74.05(2)°, andZ=2], the carboxylate groups of a pair of betaine molecules are bridged by a proton to form a dimeric cation L₂H⁺ with a very strong asymmetric hydrogen bond of length 2.464(7) Å. The crystal structure features a hydrogen-bonded corrugated ribbon comprising an alternate arrangement of edge-sharing centrosymmetric (H₂O)₄(Cl^–)₂ and (H₂O)₄ rings running parallel to thea axis.     

Aquadifluoro(1,10-phenanthroline)copper(II) dihydrate: X-ray crystal structure reveals strong hydrogen bonds between ligand fluoride and lattice water molecules

C₁₂H₁₄CuF₂N₂O₃,M=335.797, monoclinic, space groupP2₁/n,a=6.985(2),b=17.406(2),c=10.581(2) Å,=92.41(2)°,V=1285(1) ų,D _c =1.736 g cm^–3,Z=4,F(000)=684,(CuK)=27.0 cm^–1, =1.5418 Å,T=20°C, crystal dimensions=0.75×0.45×0.30 mm. The structure of the title compound shows it to be [Cu(phen)F₂(H₂O)]·2H₂O with pentacoordinate-square pyramidal Cu(II), short Cu-F bonds [1.890(4) and 1.891(4) Å], and short FH-O hydrogen bonds (ca. 2.68 Å) between the complex and lattice water molecule.     

Synthesis and characterization of a novel pentacyclic C16 diketone and derivatives

The syntheses and crystal structures of pentacyclo[9.4.1.0^5,14.0^7,13.0^12,15]hexadecane-3,9-dione (2), a novel C₁₆ diketone with potential inclusion ability, and the products of the reaction of2 withn-butyllithium andmeso-erythritol (i.e.,meso-1,2,3,4-butanetetrol) are described. Crystal data:2·H₂O, orthorhombic,Pmmn,a=10.7385(8),b=9.0188(6),c=6.8411(4)Å,V=662.55(7)ų, andR=0.039 (379 reflections);3 (product from reaction withn-butyllithium), triclinic,P¯1,a=8.7192(7),b=10.9351(8),c=12.1842(8)Å,=68.933(5),=75.850(6), =80.309(6)°,V=1047.0(1)ų, andR=0.081 (1811 reflections);4 (product from reaction with erythritol), triclinic,P¯1,a=7.7224(8),b=10.1976(8),c=10.7021(9)Å,=85.405(7),=85.766(8), =76.056(7)°,V=814.0(1)ų, andR=0.052 (1471 reflections).     

Structural and spectral studies of N-trans-cinnamylidene-m-toluidine and N-trans-cinnamylidene-m-chloroaniline

N-trans-cinnamylidene-m-toluidine (1) C₁₆H₁₅N, and N-trans-cinnamylidene-m-chloroaniline (2) C₁₅H₁₂NCl form isomorphous crystals which are monoclinic, space group P2_l/c, with unit cell dimensionsa=5.967(2),b=13.793(3),c=15.048(5) Å, =91.97(3)° anda=5.868(2),b=13.788(4),c=15.191(4) Å, =91.87(3)°, respectively. The single-crystal X-ray structure determinations of the title compounds revealtrans structures. Ring (A) C_10–15 and ring (B) C_1–6, are practically planar in both structures with dihedral angels of 61.3(3) and 63.6(2)°, respectively.¹H nmr, u.v. and i.r. spectra are also reported.     

X-ray structure of 1,3-adamantane dicarbonamide

The X-ray crystal structure of 1,3-adamantane-dicarbonamide has been determined. Colourless, cube shaped crystals of C₁₂H₁₈N₂O₂ crystallize in the monoclinic space group C2/c (#15) with cell dimensionsa=7·934(3),b=15·543(3),c=9·404(2) Å, =93.63°;V=1157.4(5) ų andZ=4.1074 unique reflections withI _net >2.00(I) on refinement afforded values ofR=0.039 andR _w =0.040.     

Crystal structure of the complex between 7,7,8,8-tetracyanoquinodimethane and 1-oxide-2-phenyl-quinoline

A series of complexes between 1-oxide quinolines and 7,7,8,8-tetracyanoquinodimethane has been synthesized and one of them has been analyzed by x-ray diffraction methods. Crystals of the title compound are monoclinic (C₁₅H₁₁NO·C₁₂H₄N₄), space groupP2₁/n,a=44.525(4),b=7.326(2),c=6.531(2) Å,=90.23(3)°. The structure was solved by direct methods and refined by block-matrix least-squares to giveR=0.047 for 1865 reflections above 2(I). Molecular dimensions, interplanar distances, empirical method and IR spectra suggest a -^* interaction with very low charge-transfer in the complex.     

Crystal structures of a series of 3,7-bis-(arylazo)-1,3,5,7-tetraazabicyclo[3.3.1]nonanes

The crystal and molecular structure of a series of 3,7-bis(arylazo)-1,3,5,7-tetraazabicyclo[3.3.1] nonanes (1a–d) have been determined by single crystal X-ray diffraction analysis. All four compounds have the same feature, that the tetraazabicyclononane unit assumes a cage-like structure with the aryltriazene moieties lying parallel to one another so that the aryl rings are held together by – stacking. Crystal data: 1a C₁₇H₁₈N₁₀O₄, triclinic, space group P – 1, a = 9.8899(10), b = 13.0845(13), c = 16.458(2) Å, = 94.095(2)°, = 107.004(2)°, = 111.027(2)°, V = 1863.5(3) ų and Z = 4; 1b, C₁₉H₁₈F₆N₈, orthorhombic, space group Pbca, a = 15.3210(8), b = 10.9512(6), c = 24.5698(13) Å, V = 4122.4(4) ų and Z = 8; 1c C₁₉H₁₈N₁₀, monoclinic, space group P2₁/n a = 6.3742(6), b = 13.7343(13), c = 21.542(2)Å, = 97.738(2)°, V = 1868.8(3) ų, and Z = 4; 1d, C₁₉H₁₈N₁₀, monoclinic, space group P2₁/c, a = 18.205(2), b = 17.398(2), c = 12.784(12) Å, = 109.480(2)°, V = 3818.0(6) ų, and Z = 8.     

Crystal and molecular structure of diphenylthiosulphodiimide

The crystal and molecular structure of diphenylthiosulphodiimide, C₁₂H₁₀N₂S₃, has been solved by the symbolic addition procedure using three-dimensional CuK diffractometer data. The system is monoclinic,a = 30·41(3),b = 5·601(5),c = 7·792(8) Å, = 108·77(1) °, space groupC2/c andZ = 4. The structure was refined by full-matrix least-squares methods toR = 0·096 for 926 observed reflexions. All hydrogen positions have been determined. The molecule possesses a crystallographic diad axis through the central sulphur atom. The planes of the phenyl rings make an angle of 30·8 ° with the closely coplanar central five atoms.     

Crystal and molecular structures of three trimethylamine-boron halide adducts: (CH3)3NBCl3, (CH3)3NBBr3, and (CH3)3NBI3

X-ray diffraction data from single crystals of the trimethylamine complexes of the three boron halides, BCl₃, BBr₃, and BI₃, lead to aP2₁/m monoclinic cell containing two molecules for each complex. The unit cell dimensions area = 6·68(1),b = 10·247(3),c = 6·502(6) Å, =116·2(1)° (chloro);a = 6·86(1),b = 10·612(4),c = 6·737(6) Å, = 115·8(1)° (bromo);a = 6·92(2),b = 10·86(1),c = 7·147(6) Å, = 93·9(1)° (iodo). The structures were solved by three-dimensional sharpened Patterson functions and show only the chloro and bromo compounds to be isomorphous. Refinement of 662,718 and 954 observed reflexions for the chloro, bromo and iodo complexes, respectively, using anisotropic thermal parameters yielded conventionalR factors of 0·045, 0·087 and 0·054.The molecules are shown to possess a B—N dative bond, a staggered conformation, and effective 3m (C _3v) symmetry. Average C—N bond lengths are 1·52(1) Å for all three complexes. Boronhalogen bond lengths average 1·864(4), 2·04(2) and 2·28(2) Å, while B—N bond distances are 1·609(6), 1·60(2) and 1·58(3) Å, respectively, for the chloro through iodo compounds. Bond angles are approximately tetrahedral with the C—N—C angle decreasing by several degrees in the Cl Br I series.Based in part on a dissertation submitted by Patty H. Clippard to the Rackham School of Graduate Studies of the University of Michigan, January 1969 in partial fulfillment of the requirements of the Ph.D. Degree.     

Crystal structure of two tricyclic antidepressant drugs: Lofepramine hydrochloride and dothiepin hydrochloride

The structures of lofepramine·HCl (1) [C₂₆H₂₇ClN₂O·HCl, triclinic, space groupP¯1, witha=17.273(8),b=9.451(7),c=7.447(5) Å,=101.88(5),=96.14(6), =96.38(5)°,Z=2] and dothiepin·HCl (2) [C₁₉H₂₁NS·HCl, monoclinic, space groupP2₁/c, witha=14.296(5),b=9.364(3),c=13.724(3) Å,=97.77(3)°,Z=4] were determined by the symbolic-addition procedure and refined by least-squares methods to anR of 0.045 (2253 diffractometer-measured reflections) for (1) and 0.051 (1696 reflections) for (2). The butterfly angle between the two aromatic ring mean planes in the tricyclic system is 123.7° in (1) and 126.2° in (2); the middle seven-membered heteroring shows twist, bow, and stern angles of 18.1, 127.6, and 149.2° for (1) and 14.6, 132.8, and 155.5° for (2). The configuration at the propylamino C(16)-C(17) and C(17)-C(18) bonds of the side chain in (1) is close totrans-trans and in both compounds the only approach less than van der Waals distances is the hydrogen bond between the positively charged dimethylammonium and the chloride ion [3.01 and 2.96 Å for (1) and (2), respectively].     

Di-2-pyridylketone semicarbazone as ligand in metal complexes: synthesis and X-ray crystal structure

A series of complexes of di-2-pyridylketone semicarbazone (Hdips) and Mn(II), Co(II), Co(III), Ni(II) and Cu(II) nitrates were synthesized and characterized by means of IR spectroscopy and for cobalt and nickel by X-ray crystal structures. The results are in agreement with the formulae: Mn(Hdips)₂(NO₃)₂·2H₂O, [Co(Hdips)₂](NO₃)₂·H₂O (I), [Ni(Hdips)₂](NO₃)₂·H₂O (II), Cu(Hdips)(NO₃)₂·2H₂O, [Co(dips)₂](NO₃)·2H₂O (III). The structure of I and II are monoclinic, space groupP2₁/c, with, I,a=15.980(4),b=11.531(2),c=16.170(2)Å;=104.20(2)°,Z=4,R=0.032; II,a=16.109(5),b=11.480(3),c=16.135(6)Å;=104.15(2)°,Z=4,R=0.069. Compound III is also monoclinic, space groupP2₁/c witha=12.173(5),b=15.619(5),c=15.338(8)Å;=111.40(4)°,Z=4,R=0.059. In these complexes the ligand is tridentate via carbonylic oxygen, semicarbazone and pyridine nitrogens forming each two five membered chelate rings with the metal in a distorted octahedral geometry.     

Primary to secondary sphere coordination of 15-crown-5 to lanthanide(III) chlorides: structural analysis of [MCl3(15-crown-5)] (M=La,Ce) and [Er(OH2)8]Cl3·15-crown-5

Complexes of LaCl₃·7H₂O and CeCl₃·7H₂O directly coordinated to 15-crown-5 were prepared by placing the reactants in 31 CH₃CNCH₃OH on opposite sides of a fine porosity glass frit in a U-shaped cell and passing a 10 A current through the cell. The crystal structures of the two anhydrous 8-coordinate complexes, [MCl₃(15-crown-5)] (M=La, Ce) have been determined. Each contains the lanthanide in a bicapped trigonal prismatic geometry. The two complexes are isostructural crystallizing in the monoclinic space groupP2₁/c with (at 20°C) for M=La:a=8.217(8),b=14.298(2),c=14.341(9) Å, =104.79(8)°, andD _calc=1.90 g cm^–3 forZ=4; for M=Ce:a=8.208(9),b=14.263(6),c=14.270(8) Å, =104.74(7)°, andD _calc=1.92 g cm^–3 forZ=4. Direct reaction of ErCl₃·6H₂O with 15-crown-5 in 31 CH₃CNCH₃OH resulted in the crystallization of the second sphere hydrogen bonded complex [Er(OH₂)₈]Cl₃·15-crown-5. This complex is monoclinic,P2₁/n with (at 18°C)a=9.193(3),b=17.235(9),c=15.216(5) Å, =92.48(3)°, andD _calc=1.76 g cm^–3 forZ=4. The Er³⁺ ion is dodecahedral.     

Hydrogen bonding in 2-hydroxy((di)thio)benzoates. II. X-ray structures of tetraethylammonium salts

X-ray structural data are reported for tetraethylammonium-2-hydroxythiobenzoate (C₁₅H₂₅NO₂S; orthorhombic,Pna2₁(33);a=14.155(2)Å,b=7.651(1)Å,c=14.855(2)Å;Z=4;R=0.038, at 295 K) and for tetraethylammonium-2-hydroxydithiobenzoate (C₁₅H₂₅NOS₂; orthorhombic,Pna2₁(33);a=15.668(4)Å,b=8.729(2)Å,c=12.350(3)Å;Z=4;R=0.031, at 295 K). In both compounds the OH groups are engaged in intramolecular O-HS hydrogen bonds (OS=2.88 and 2.89 Å, respectively).