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1.
The structure of the title compound, C18H23N3O4, was determined by X-rays.M r =344.40, triclinic, space groupP¯1,a=8.163(4),b=9.230(2),c=13.297(2) Å,=102.70(2),=103.58(3)°,=102.50(3)°,V=911.3 Å3,Z=2,D c =1.26 Mg m–3. CuK radiation (graphite crystal monochromator,=1.54178 Å),(CuK)=7.50 cm–1,T=290 K. Final conventionalR-factor=0.068,R w =0.079 for 1912 unique reflections and 295 variables. The structure was solved usingMultan andDirdif. The title compound is the first example of a 3,6-tetrasubstituted dioxopiperazine adopting a folded conformation, owing to a direct interaction between the dioxopiperazine ring and the aromatic side chain.  相似文献   

2.
(3(Z),4,6a,9a,9b)-(±)-3a,4,6a,7,8,9,9a,9b-octahydro-4,7,7, 9b-tetramethyl-3a-[3-(methoxymethyloxy)-3-methyl-1-butenyl]-5H-naphto[1,8-de]-1,3-dioxin-6-one (I), C22H36O5,M r=378.51, monoclinic,P21/n,a=6.330(1),b=14.576(2),c=22.837(2)Å,=93.04(1)°,V=2104.1(2)Å3,Z=4,D c=1.19 Mg/m3, (MoK)=0.71069Å,=0.8 cm–1,F(000)=832,T=298 K,R=0.054 for 1971 observed reflections; (7a,10a,10b,12)-(±)-7a,9, 10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6,-de][1,3,2]-benzodioxin-11-one (II), C20H29O4,M r=334.5, triclinic,P-1,a=10.595(2),b=12.152(1),c=8.073(1)Å,=106.53(1),=105.65(1), =66.29(1)°,V=897.9(2)Å3,Z=2,D c=1.24 Mg/m3, (MoK)=0.71069Å,=0.8 cm–1,F(000)=362,T=298 K,R=0.046 for 2848 observed reflections; (7a,10a,10b,12, 12a)-(±)-7a,9,10,10a,10b,11,12,12a-octahydro-2,2,10,10,10b,12a-hexamethyl-2H,8H-1-benzopyrano[4a,5,6-de][1,3,2]-benzodioxin-11, 12-diol (III), C20H32O5 (two molecules in the asymmetric unit),M r=352.2, triclinic,P-1,a=12.948(3),b=13.615(3),c=12.197(4)Å,=101.16(2),=111.88(2), =69.48(2)°,V=1863.8(9)Å3,Z=2,D C=1.26 Mg/m3,(MoK)=0.71069 Å,=0.8 cm–1,F(000)=768,T=298 K,R=0.060 for 4570 observed reflections; 4-acetoxy-4-[[(4a,5,8a)-(±)-hexahydro-4a,6,6-trimethyl-4H-1,3-benzodioxin-4-one]-5-yl]butan-2-one (IV), C17H26O6,M r=326.4, monoclinic,P21/c,a=10.495(2),b=12.050(2),c=14.216(2)Å,=108.51(1)°,V=1704.8(5)Å3,Z=4,D c=1.27 Mg/m3,(MoK)=0.71069 Å,=0.9 cm–1,F(000)=704,T=298 K,R=0.049 for2455 observed reflections; (3a,4,5,6,6a,9a,9b)-(±)-4,5-epoxy-decahydro-3, 3a-dihydroxy-2-ethoxy-4,7,7,9b-tetramethyl-naphto-[1,8-bc]-pyran-6-ol-acetate (V), C20H32O7,M r=383.5, monoclinic,C2/c,a=10.353(2),b=17.975(3),c=21.188(3)Å,=91.29(1)°,V=3942(1)Å3,Z=8,D c=1.29 Mg/m3,(MoK)=0.71069 Å,=0.8 cm–1,F(000)=1664,T=298 K,R=0.051 for 2120 observed reflections. We report here the complete structures of four decalin derivatives (compoundsI, II, III, V) and one related compound (compoundIV) synthetized in order to find an efficient synthetic approach for the natural productforskolin.  相似文献   

3.
The structure of the title compound, C19H20O5S, was determined by X-rays.M r =360.42, monoclinic, space groupP21/c, a=8.517(2),b=31.107(2),c=20.517(4) Å,=96.205(18)°,V c =5403.9 Å3,Z=12,D x =1.45 Mg m–3. CuK radiation (graphite crystal monochromator, =1.54178 Å),(CuK)=1.777 mm–1,F(000)=2280T=295 K. Final conventionalR-factor=0.058,R w =0.060 for 3476 observed reflections and 552 variables. The structure was solved usingMultan andDirdif (direct methods applied to difference structures). The configurations of three crystallographically independent molecules in the asymmetric unit of the crystal are reported.  相似文献   

4.
Two labdane diterpenoids, labda-7,12(E),14-triene-17-oic acid (1) and labda-12(Z),14,17-triene-18-oic acid (2), C20H30O2, have been isolated from Croton oblongifolius. Both 1 and 2 crystallized in the monoclinic system, space group C2, with cell dimensions of a = 21.912(1) Å, b = 7.4002(4) Å, c = 11.5079(7) Å, = 101.999(1)o and a = 21.308(2) Å, b = 11.9067(9) Å, c = 7.5606(6) Å, = 100.763(1)o, respectively. Compound 1, a rare example of carboxylic group bound to a cyclohexene ring, forms an infinite intermolecular hydrogen-bonded polymer [O1 O2(–x + 1/2, y + 1/2, –z + 2) 2.697(2) Å], whereas molecules of compound 2 are linked to form an asymmetric hydrogen-bonded dimer [O1 O2(–x, y, –z) 2.657(3) Å].  相似文献   

5.
The structure of the title compound, C12H16O3, was determined by X-rays.M r =208.26, triclinic, space groupP¯1,a=7.802(2),b=8.449(2),c=9.069(1) Å,=90.79(1)°,=105.57(1)°, =106.07(1)°,Z=2,D x =1.26 Mg m–3; MoK radiation (graphite crystal monochromator, =0.71069 Å),(MoK)=0.96 cm–1,T=290 K. Final conventionalR-factor=0.046,R w =0.067 for 3009 observed reflections and 184 variables. The structure was solved using Patterson methods andDirdif, and the resulting all cis-endo configuration of the alcohol group on C(3) and the ethoxy group on C(5) shows that the stereochemistry of the metal-mediated addition reaction involved is solely determined by steric factors.  相似文献   

6.
The crystal structure of 2,2-bis-1,3-dithiole dimethyl dicyanofumarate has been determined from a single-crystal X-ray study. The compound crystallizes in the monoclinic space groupP21/c with two complexes per unit cell of dimensionsa=11.075(2)Å,b=11.615(3)Å,c=6.623(4)Å, ==90.0°,=95.7(16)°, andV=847.6(9)Å3. The observed and calculated densities are 1.56 and 1.57 g cm–3 respectively. Full-matrix least-squares refinement using 404 reflections having 4°250° andI3(I) converged atR=0.0492 andR w =0.0614. Structural parameters in bond lengths and bond angles do not change to any observable extent when comparing the parent molecules to the complexed state. AnOrtep view along thec-axis shows the units to be arranged in segregated parallel stacks with a distance of 3.31 Å between layers.We are indebted to the US Army Research Office, Grant DAAG-29-77-G-0231, for support of the research and to Dr. J. H. Enemark and Dr. W. Setzer for their professional advice.  相似文献   

7.
The title compound, 1-(2,3-dideoxy-3-fluoro--d-erythro pentofuranos-1-yl)-5-chlorocytosine, crystallises in the orthorhombic space groupP212121 witha=5.142(1),b=14.177(2),c=15.721(2) Å,Z=4. The crystal structure was solved by the heavy atom method and refined by full-matrix least-squares method to a finalR value of 0.031 for 1629 unique observed reflections. The N-glycosidic torsion angle is –156.1(2)° and the sugar moiety is anti to the cytosine base. The sugar pucker is 2 3 T withP=178.2(1)° and=31(1)°. The atom 05 is in a +sc conformation with respect to the furanose ring. The molecular packing in the crystal is stabilized by N-HN, N-HO, O-HO hydrogen bonds and C-HO close contacts.  相似文献   

8.
C12H3Cl6O4, (I),M r=428.91, triclinic, ,a=9.197(1),b=9.336(2),c=9.830(1) Å, =79.29(1), =83.33(1), =85.38(1)°,V=822.16,Z=2,D x=1.73 Mg m–3,F(000)=428, (MoK)=0.71069 Å, =10.62 cm–1, room temperature, finalR=0.033 for 2573 unique counter reflections withF o>4(F o). C13H10Cl6O3, (II),M r=426.94, triclinic, ,a=9.374(2),b=9.503(1),c=9.888(4) Å, =79.26(2), =82.10(3), =84.43(1)°,V=854.88,Z=2,D c=1.66 Mg m–3,F(000)=428, =0.71069 Å, =10.17 cm–1, room temperature, finalR=0.030 for 2609 unique counter reflections withF o>4(F o). Compounds I and II are isostructural. Centrosymmetric dimers are formed by hydrogen bonds from the two methine hydrogen atoms to the carbonyl oxygen atom. The dimers are linked by Cl...(Ar)...Cl, Cl...O and Cl...Cl interactions to form a three-dimensional pattern. The geometry associated with these interactions is discussed in terms of the electrophile: nucleophile model.  相似文献   

9.
Reaction of an excess of trimethylaluminum with bis(diphenylphosphino)-methane in heptane affords the crystalline complex [A1(CH3)3]2[(C6H5)2PCH2P(C6H5)2]. The title compound crystallizes in the triclinic space group P¯1 with unit cell parametersa=10.053(6),b=11.017(6),c=15.908(8) Å,=85.58(4),=71.80(4), =77.49(4)°,V=1634(1) Å3, andD c=1.07 g cm–3 forZ=2. Least-squares refinement based on 2924 observed reflection with intensitiesI3I) in the range 2.00245.0° converged atR=0.050 (R w=0.067). The Al-P distances are 2.585(2) and 2.521(2) Å, and the P-C-P angle is 121.4(2)°.  相似文献   

10.
A series of ternary complexes of copper(II), cobalt(II) and zinc(II) with L-histidine, 1,10-phenanthroline, 2,2-dipyridyl or imidazole having perchlorate or acetate as counterions were synthesized and characterized by conventional methods and for [Cu(bipy)(L-hist)]ClO4·1.5H2O and X-ray crystal structure was determined. The crystals belong to the monoclinic space groupC2 witha=18.843(3),b=10.582(2),c=11.020(2), =115.20(10)°,Z=4,R=0.0535. The structure is consistent of [Cu(bipy)(L-hist)]+ cations, perchlorate ions and water molecules. The geometry around copper is trigonal bipyramidal with one N,N,O tridentate L-histidine molecule and one 2,2-dipyridyl ligand, the apical sites are occupied by the -amino nitrogen [Cu–N(71) 1.995(8)] and by N(11) of 2,2-dipyridyl [Cu–N(11) 1.983(7)], the equatorial plane is formed by the N(3) imidazole -nitrogen [Cu–N(3) 2.140(6)], O(82) carboxylic oxygen [Cu–O(82) 2.009(5)] and N(22) [Cu–N(22) 2.010(7)].  相似文献   

11.
The title compound crystallizes in the orthorhombic space groupP212121 witha=5.084(1),b=14.322(3),c=16.065(2)Å,Z=4. The structure was solved by the heavy atom method and refined by full-matrix least-squares calculations to a finalR value of 0.033 for 1106 unique observed reflections. The N-glycosidic torsion anglex has a value of –153.7(4)°, in the anti-range. The sugar pucker is2T3 withP=175(1)° and=30(1)°. The C4-C5 conformation is + sc with =46.7(7)°. The structure is stabilized by N-HN, N-HO and O-HO hydrogen bonds and C-HO close contacts.  相似文献   

12.
A new cytotoxic macrocyclic diterpenoid named Japodagrol, C20H28O4, has been isolated from the ornamental plantJatropha podagrica, family Euphorbiaceae, grown in Nigeria. The structure of the title compound, C20H28O4, was solved by X-ray analysis.M r =332.44, monoclinic space groupC2,a=23.285(4),b=6.5105(12),c=12.505(3) Å,=98.504(17),V=1874.8 Å3,Z=4,D c =1.178 Mg/m3. CuK radiation (graphite crystal monochromator, =1.54184 A), (CuK)=6.13 cm–1,F(000)=720,T=290 K. Final conventionalR factor=0.035,R w =0.038 for 3349 observed reflections. The structure was solved with the programDirdif. The 5-membered ring is closed to a half-chair form. The compound contains inter- and intramolecular hydrogen bonds.  相似文献   

13.
The crystal structure of 17-methyltestosterone hemihydrate, C20H30O2·1/2H2O, has been determined:M r =312.5, space groupP21212121,a=6.374(2),b=12.807(2),c=43.398(5)Å,V c =3543(2)Å3,Z=8,D x =1.172 mg–3, CuK radiation ( = 1.54184 Å),(CuK)=5.5 cm–1,F(000)=1376. The structure was solved usingMultan. The final conventionalR=0.053 (R w =0.052) for 3634 reflections. The structure contains two crystallographically independent molecules in the asymmetric part of the unit cell that have almost identical geometry.  相似文献   

14.
2(C12H26O3N3·C2H3O2)·C2H4O2·H2O,M r =350.44, triclinic, P1,a=5.576,b=12.574(3),c=14.946(2) Å, =107.80(2), =96.34(2), =89.89(2)°.B=991.04(6) Å3,Z=2,D x =1.201 g/cm3, (KCu)=1.5418, Å, =7.4 cm–1, room temperature.R=0.074 for 2645 observed reflections. In the unit cell there are two peptide molecules, three acetic acid molecules, two of them likely to be present as acetate anions, and one water molecule. Each peptide exists in zwitterionic form with the carboxylic group deprotonated, and with positive charges both in the amino terminal and -amino groups of lysine. The two peptide molecules have almost identical conformations. The dipeptide backbone is folded.  相似文献   

15.
The structure of the title compound, C10H9BrO2, was determined by X-rays.M r =241.08, triclinic, space groupP¯1,a=5.800(1),b=6.441(1),c=12.030(1) Å,=92.90(1)°,=95.65(2)°, =95.69(2)°,V c =444.2 Å3,Z=2,D x =1.80 Mg m–3, MoK radiation (graphite crystal monochromator, =0.71069 Å),(MoK)=48.58 cm–1,T=290 K. Final conventionalR-factor=0.037,R w =0.044 for 1863 observed reflections and 145 variables. The structure was solved usingMultan andDirdif. The results show that the 5-bromo substituent has a marked effect on the geometry of the homocubane skeleton. Its presence prevents a complete release of geometrical strain and induces a shortening of the bond distances to the apex carbon atom.  相似文献   

16.
The structure of the title compound, C18H20N2O5, was determined by X-rays atT=290 K.M r =344.366, monoclinic, space groupP21/c,a=13.7850(8),b=8.8951(7),c=15.1603(11) Å, =111.410(6)°,V c =1730.7 Å3,Z=4,D x =1.322 Mgm–3. Cu K radiation (graphite crystal monochromator, =1.54178 Å),(Cu K)=7.69 cm–1. Final conventionalR-factor=0.057,R w =0.076 for 2160 observed reflections and 271 variables. The structure was solved usingMultan.  相似文献   

17.
The crystal structures of [(5-C5H4COOH)W(CO)3R] (R=Me, I) have been determined. They crystallize in two different monoclinic space groups. R=Me isP21/c,a=10.4833(6),b=8.0144(7),c=13.0731(6) , =93.147(4)°, andD(calc)=2.374 g-cm–3 forZ=4. R=I isP21/n,a=7.814(2),b=13.075(4),c=11.097(4) , =91.75(2)°, andD(calc)=2.953 g-cm–3 forZ=4. Both possess a four-legged piano stool geometry. The methyl ligand in the R=Me complex is disordered between two positions insyn oranti relative to the substituted carbon of the cyclopentadienyl ligand. The iodo ligand in the R=I complex is, however, exclusively insyn-position.  相似文献   

18.
The title compound is orthorhombic,M r =590.2,P212121 (No. 19),a=9.865(2),b=9.924(2),c=31.202(7) Å,V=3055(2) Å3,Z=4,D x =1.283 g cm–3, (MoK );F(000)=1256; (MoK )=6.76 cm–1, finalR=0.052 for 1441 reflections I2.5(I). The nitrite group is chelated via the two oxygen atoms; the two six-membered rings resulting from the coordination of the 1,3-propanediamine ligands to the nickel(II) atom are in the chair conformation. The Ni-N and Ni-O distances average 2.07(1) and 2.14(2) Å respectively. The two Ni-O distances are nearly equivalent.  相似文献   

19.
The preparation and X-ray crystal structures of two polymorphs of the antibacterial drug nitrofurantoin are reported. The -polymorph is triclinic, space groupP¯1 witha=6.774(1),b=7.795(1),c=9.803(2)Å, =106.68(1),=104.09(2), =92.29(1)°,Z=2. The-polymorph is monoclinic, space groupP21/n witha=7.840(5),b=6.486(1),c=18.911(6)Å,=93.17(3)°,Z=4. The nitrofurantoin molecules adopt the same, planar conformation in both polymorphs. Both crystal structures are built up from layers held together by van der Waals forces. In each polymorph, intralayer cohesion is effected by N-HO and C-HO hydrogen bonds, but their arrangements differ in the two crystals. The significance of the C-HO hydrogen bond, now known to occur in four modifications of nitrofurantoin, is discussed.  相似文献   

20.
The present compound crystallizes in the space groupP212121 withZ=4 and cell parametersa=21.687(2),b=8.155(3),c=5.883(2)Å. The structure was solved by direct methods and refined by full-matrix least-squares to a finalR value of 0.045 for 1153 observed reflections. The N-glycosidic torsion angle CN is in the anti-range and the pyranosyl ring adopts a distorted half-chair conformation with 2=142.7(4)°, 2=124.4(3)° andQ=0.456(2)Å. In the crystal packing the molecules are linked together by N-HO hydrogen bonds and C-HO contacts.  相似文献   

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