Home Structural elucidation of 1-(3-acetyl-2,6-dihydroxy-4-methoxyphenyl)-4,5-dihydroxy-2-methylanthracene-9,10-dione isolated from Bulbine latifolia (L.) Wild, C24H18O8
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Structural elucidation of 1-(3-acetyl-2,6-dihydroxy-4-methoxyphenyl)-4,5-dihydroxy-2-methylanthracene-9,10-dione isolated from Bulbine latifolia (L.) Wild, C24H18O8

  • Buyiswa G. Hlangothi EMAIL logo , Lungelwa Mahanjana , Eric C. Hosten ORCID logo , Fanie R. van Heerden and Maryna van de Venter
Published/Copyright: June 1, 2020

Abstract

C24H18O8, monoclinic, P21 (no. 4), a = 7.9654(3) Å, b = 23.6910(8) Å, c = 21.2314(8) Å, β = 96.777(2)°, V = 3978.6(3) Å3, Z = 8, Rgt(F) = 0.0499, wRref(F2) = 0.1320, T = 200 K.

CCDC no.: 1837444

One of the four crystallographically independent title molecules is shown in the figure. Table 1 contains crystallographic data and Table 2 contains the list of the atoms including atomic coordinates and displacement parameters.

Table 1:

Data collection and handling.

Crystal:Orange block
Size:0.53 × 0.47 × 0.07 mm
Wavelength:Mo Kα radiation (0.71073 Å)
μ:0.11 mm−1
Diffractometer, scan mode:Bruker APEX-II, φ and ω
θmax, completeness:28.4°, >99%
N(hkl)measured, N(hkl)unique, Rint:36555, 17766, 0.025
Criterion for Iobs, N(hkl)gt:Iobs > 2 σ(Iobs), 14484
N(param)refined:1181
Programs:Bruker [1], SHELX [2], [3], [4], WinGX/ORTEP [5], PLATON [6], Mercury [7]
Table 2:

Fractional atomic coordinates and isotropic or equivalent isotropic displacement parameters (Å2).

AtomxyzUiso*/Ueq
O11−0.0316(7)0.25062(15)−0.22112(14)0.0876(15)
H11−0.0687790.283150−0.2302570.131*
O12−0.1123(7)0.35244(15)−0.19848(14)0.0926(16)
O13−0.1921(9)0.45747(18)−0.17954(18)0.119(2)
H13−0.1733810.429302−0.2017010.178*
O140.0573(4)0.32213(12)0.05060(12)0.0499(7)
O15−0.2436(3)0.23125(11)0.03805(12)0.0375(6)
H15−0.3258410.2295690.0593560.056*
O16−0.3989(3)0.21237(13)0.13061(14)0.0473(7)
O170.0312(4)0.14728(16)0.22593(13)0.0570(8)
O180.3275(3)0.18595(15)0.04826(13)0.0515(7)
H180.4109380.1812140.0758450.077*
O210.3543(8)0.57196(17)−0.11549(16)0.1054(18)
H210.3538160.545354−0.1416520.158*
O220.3550(9)0.46968(17)−0.15170(17)0.113(2)
O230.3555(10)0.36741(19)−0.19338(17)0.121(2)
H230.3360890.402222−0.1962290.182*
O240.4703(5)0.39538(14)0.08811(13)0.0599(8)
O250.7305(4)0.51301(16)0.13786(14)0.0574(8)
H250.8241670.5076730.1596400.086*
O260.9313(3)0.49251(18)0.23348(16)0.0682(10)
O270.5304(3)0.45055(13)0.32943(12)0.0427(6)
O280.1525(3)0.48688(17)0.14285(13)0.0598(9)
H280.0825680.4860260.1695030.090*
O31−0.0630(5)0.21561(12)0.63132(12)0.0520(7)
H31−0.0369400.2407800.6585850.078*
O32−0.0281(5)0.31812(12)0.66707(12)0.0569(8)
O330.0097(7)0.42052(15)0.70750(15)0.0834(13)
H33−0.0094160.3857730.7099810.125*
O340.1162(4)0.38255(12)0.43671(13)0.0527(8)
O350.2738(3)0.26875(15)0.38392(12)0.0500(7)
H350.3549350.2720780.3622720.075*
O360.4182(3)0.28441(19)0.28772(14)0.0679(11)
O37−0.0337(3)0.33412(12)0.19092(11)0.0395(6)
O38−0.3033(3)0.29964(16)0.37554(12)0.0532(8)
H38−0.3890470.3022110.3485730.080*
O410.4737(5)0.53365(13)0.72964(13)0.0562(8)
H410.4929790.5004400.7423480.084*
O420.5036(5)0.42735(13)0.71254(13)0.0627(9)
O430.4570(7)0.31857(14)0.68929(17)0.0827(13)
H430.4520930.3482300.7106790.124*
O440.7189(3)0.45947(12)0.48904(12)0.0428(6)
O450.2774(3)0.56433(10)0.46052(11)0.0314(5)
H450.1935660.5669590.4327020.047*
O460.1175(3)0.58438(11)0.35651(12)0.0381(6)
O470.5589(3)0.63485(14)0.29130(13)0.0513(7)
O480.8734(3)0.56851(13)0.47944(14)0.0485(7)
H480.8709030.5375200.4985330.073*
C1010.0326(4)0.22279(15)−0.02676(15)0.0325(7)
C1020.0456(5)0.17867(15)−0.07115(17)0.0364(8)
C1030.0757(6)0.11851(16)−0.05031(19)0.0459(9)
H10A0.0520380.093374−0.0869460.069*
H10B0.0010230.108970−0.0183710.069*
H10C0.1937960.113953−0.0320370.069*
C1040.0291(6)0.19077(16)−0.13510(18)0.0455(9)
H1040.0460520.161481−0.1642520.055*
C105−0.0114(7)0.24417(19)−0.15803(18)0.0551(11)
C106−0.0298(6)0.28883(17)−0.11547(17)0.0449(9)
C107−0.0814(7)0.34465(19)−0.14012(19)0.0569(12)
C108−0.0990(7)0.39091(18)−0.09614(19)0.0521(10)
C109−0.1528(8)0.4450(2)−0.1183(2)0.0691(15)
C110−0.1681(9)0.4882(2)−0.0747(3)0.0752(16)
H110−0.2083580.524232−0.0890440.090*
C111−0.1252(10)0.4785(2)−0.0112(2)0.0824(19)
H111−0.1349270.5084080.0180200.099*
C112−0.0678(7)0.42625(18)0.0116(2)0.0612(13)
H112−0.0364200.4206690.0557500.073*
C113−0.0568(6)0.38213(16)−0.03082(17)0.0427(9)
C1140.0043(5)0.32637(15)−0.00514(16)0.0361(7)
C115−0.0003(5)0.27733(15)−0.04947(15)0.0360(7)
C1160.0394(4)0.20743(15)0.04123(15)0.0315(7)
C1170.1841(4)0.18686(16)0.07652(16)0.0351(7)
C1180.1849(5)0.16658(18)0.13832(17)0.0415(9)
H1180.2861950.1521170.1605950.050*
C1190.0388(5)0.16757(17)0.16685(16)0.0372(8)
C1200.1801(8)0.1236(4)0.2591(3)0.101(3)
H12A0.2171830.0915370.2350730.152*
H12B0.1562420.1107030.3009950.152*
H12C0.2694190.1522430.2641110.152*
C121−0.1125(4)0.18991(14)0.13514(15)0.0302(7)
C122−0.2715(4)0.19222(15)0.16205(17)0.0355(7)
C123−0.2935(5)0.1725(2)0.22775(19)0.0506(10)
H12D−0.4074670.1821560.2373290.076*
H12E−0.2096630.1910640.2584220.076*
H12F−0.2778550.1315440.2304020.076*
C124−0.1062(4)0.20941(14)0.07184(15)0.0293(6)
C2010.4150(4)0.51458(16)0.07078(17)0.0365(8)
C2020.3967(5)0.57272(17)0.05537(18)0.0432(9)
C2030.4008(7)0.6168(2)0.1066(2)0.0606(12)
H20A0.3790450.6540370.0872700.091*
H20B0.5122860.6167540.1317270.091*
H20C0.3138630.6083060.1342620.091*
C2040.3748(6)0.58944(19)−0.0070(2)0.0548(11)
H2040.3619290.628464−0.0166290.066*
C2050.3709(8)0.5509(2)−0.0560(2)0.0648(14)
C2060.3866(6)0.49291(18)−0.04296(19)0.0512(10)
C2070.3784(8)0.4528(2)−0.0954(2)0.0681(15)
C2080.3967(7)0.39271(19)−0.0828(2)0.0535(11)
C2090.3906(8)0.3531(2)−0.1321(2)0.0670(14)
C2100.4138(7)0.2961(2)−0.1180(2)0.0639(13)
H2100.4118410.269346−0.1514560.077*
C2110.4393(6)0.27833(19)−0.0567(2)0.0559(11)
H2110.4539690.239215−0.0478460.067*
C2120.4444(6)0.31668(18)−0.0064(2)0.0488(10)
H2120.4601020.3038370.0362890.059*
C2130.4261(5)0.37344(17)−0.01984(18)0.0420(9)
C2140.4367(5)0.41352(17)0.03494(17)0.0402(8)
C2150.4104(5)0.47506(16)0.02136(16)0.0376(8)
C2160.4437(4)0.49852(15)0.13950(16)0.0328(7)
C2170.6043(4)0.49794(16)0.17197(18)0.0370(8)
C2180.6402(4)0.48180(15)0.23664(16)0.0332(7)
C2190.8140(4)0.48031(17)0.26578(19)0.0411(8)
C2200.8665(4)0.46511(19)0.33341(19)0.0441(9)
H22A0.8206070.4279530.3422830.066*
H22B0.8232710.4933920.3610710.066*
H22C0.9902160.4639900.3413170.066*
C2210.4993(4)0.46688(15)0.26840(16)0.0320(7)
C2220.3907(4)0.43634(18)0.36285(17)0.0408(8)
H22D0.3149240.4689040.3630730.061*
H22E0.4324110.4259440.4065870.061*
H22F0.3290570.4044330.3418220.061*
C2230.3379(4)0.46970(17)0.23724(16)0.0359(8)
H2230.2439130.4612740.2593070.043*
C2240.3119(4)0.48486(17)0.17352(17)0.0376(8)
C301−0.0063(4)0.26989(14)0.44886(15)0.0291(6)
C302−0.0377(5)0.21291(16)0.46279(16)0.0370(8)
C303−0.0572(7)0.16948(18)0.41074(19)0.0537(11)
H30A−0.1545210.1792220.3800050.081*
H30B−0.0752170.1322570.4289280.081*
H30C0.0453190.1686810.3893960.081*
C304−0.0500(5)0.19638(16)0.52447(18)0.0417(8)
H304−0.0675790.1576640.5333500.050*
C305−0.0372(5)0.23504(15)0.57344(17)0.0375(8)
C306−0.0008(4)0.29194(14)0.56167(14)0.0306(7)
C3070.0040(5)0.33308(15)0.61296(16)0.0371(8)
C3080.0452(5)0.39190(15)0.60106(16)0.0361(7)
C3090.0476(6)0.43288(17)0.64897(19)0.0491(10)
C3100.0928(6)0.48818(17)0.6371(2)0.0511(10)
H3100.0952100.5158480.6695420.061*
C3110.1341(5)0.50268(15)0.57822(18)0.0397(8)
H3110.1660850.5404470.5704350.048*
C3120.1299(4)0.46300(15)0.52982(17)0.0356(7)
H3120.1589630.4735860.4893340.043*
C3130.0830(4)0.40800(14)0.54097(15)0.0294(6)
C3140.0749(4)0.36764(15)0.48761(15)0.0319(7)
C3150.0197(4)0.30816(14)0.49858(15)0.0274(6)
C316−0.0109(4)0.28635(14)0.38081(14)0.0292(6)
C3170.1310(4)0.28593(15)0.34965(15)0.0311(7)
C3180.1294(4)0.30152(15)0.28427(15)0.0297(7)
C3190.2839(4)0.29940(18)0.25526(17)0.0403(8)
C3200.2970(5)0.3141(2)0.18779(18)0.0491(10)
H32A0.2167630.2911510.1600890.074*
H32B0.4121930.3065020.1780790.074*
H32C0.2707970.3541410.1808100.074*
C321−0.0304(4)0.31782(14)0.25198(14)0.0287(6)
C322−0.1936(5)0.34819(17)0.15657(16)0.0389(8)
H32D−0.1788350.3561560.1122730.058*
H32E−0.2398190.3816110.1755920.058*
H32F−0.2718050.3164390.1583340.058*
C323−0.1731(4)0.31657(15)0.28211(15)0.0308(7)
H323−0.2793220.3263100.2596160.037*
C324−0.1626(4)0.30101(15)0.34585(15)0.0323(7)
C4010.5644(4)0.55531(14)0.54196(15)0.0287(6)
C4020.5219(4)0.60098(15)0.57991(17)0.0350(7)
C4030.5049(5)0.65997(15)0.55344(19)0.0421(8)
H40A0.4812700.6861880.5869880.063*
H40B0.4119380.6611710.5188410.063*
H40C0.6104670.6709250.5372570.063*
C4040.4947(5)0.59203(15)0.64212(16)0.0372(8)
H4040.4676300.6231280.6673110.045*
C4050.5062(5)0.53820(16)0.66860(16)0.0379(8)
C4060.5458(4)0.49213(14)0.63208(16)0.0329(7)
C4070.5328(5)0.43450(16)0.65651(17)0.0408(8)
C4080.5414(5)0.38659(15)0.61359(17)0.0372(8)
C4090.5024(6)0.33146(17)0.6321(2)0.0529(11)
C4100.5066(7)0.28751(18)0.5886(2)0.0596(12)
H4100.4753150.2504840.5998600.072*
C4110.5552(6)0.29725(18)0.5299(2)0.0545(11)
H4110.5598450.2666610.5012480.065*
C4120.5979(5)0.35090(16)0.51160(19)0.0416(8)
H4120.6332540.3570380.4709640.050*
C4130.5884(4)0.39563(14)0.55313(16)0.0319(7)
C4140.6346(4)0.45287(14)0.53310(16)0.0326(7)
C4150.5800(4)0.50157(13)0.56895(15)0.0284(6)
C4160.5713(4)0.56792(14)0.47305(15)0.0283(6)
C4170.4182(4)0.57638(13)0.43482(15)0.0265(6)
C4180.4109(4)0.59695(14)0.37165(15)0.0287(6)
C4190.2446(4)0.59968(14)0.33347(16)0.0316(7)
C4200.2224(5)0.6189(3)0.2667(2)0.0588(13)
H42A0.2466140.6593710.2650280.088*
H42B0.1057030.6118460.2481390.088*
H42C0.3001580.5981220.2426450.088*
C4210.5668(4)0.61137(16)0.34984(16)0.0353(7)
C4220.7119(6)0.6523(3)0.2687(2)0.0761(18)
H42D0.7677940.6807300.2973710.114*
H42E0.6866110.6684400.2261110.114*
H42F0.7867880.6196170.2668880.114*
C4230.7197(4)0.60250(17)0.38665(17)0.0380(8)
H4230.8233010.6122020.3713170.046*
C4240.7182(4)0.57901(15)0.44671(17)0.0359(8)

Source of material

The plant specimen of Bulbine latifolia (L.) Wild was collected from Nelson Mandela University gardens by Lungelwa Mahanjana in February 2014 and was stored in the plant room until the time of extraction. Plant authentication was performed by Dr. Paul Steyn, a botanist at Nelson Mandela University Herbarium, where a specimen of Bulbine latifolia (L.) Wild with voucher number PEU24039 has been deposited. The tubers were thoroughly washed with a hard brush to remove dirt and soil particles and then chopped into small pieces. They were then dried in an oven for a week at 40 °C until they were completely dry. The dried plant samples were ground into fine powder using an electric mill.

The ground tubers (50 g) of B. latifolia were exhaustively extracted with MeOH/CHCl3 (1:4) by cold maceration at room temperature. The extract was evaporated under reduced pressure to yield a reddish-brown crude extract (11.0 g). The extract was subjected to column chromatography (VLC: column size: 80 X 4) on silica gel (300 g) eluting with n-hexane containing increasing amounts of ethyl acetate to afford 12 major fractions ca. 200 mL each. Based on TLC profile, similar compounds were identified in the fractions; therefore the fractions were combined to yield two main fractions, fraction one and fraction two. Fraction one was chromatographed using column chromatography with the solvent system of 15% ethyl acetate in n-hexane and the collected fractions yielded yellow-orange crystals upon evaporation.

1H NMR (CDCl3, 25 °C) δ (400 MHz, ppm): 14.10 (s, 1H, OH-2′), 12.52 (s, 1H, OH-1), 11.88 (s, 1H, OH-8), 7.51 (m, J = 7.9 Hz, 1H, H-6), 7.53 (m, J = 7.8 Hz, 1H, H-5), 7.22 (s, 1H, H-2), 7.17 (d, J = 5.6 Hz, 1H, H-7), 6.08 (s, 1H, H-5′), 3.88 (s, 3H, OCH3), 2.59 (s, 3H, CO—CH3), 2.09 (s, 3H, CH3). 13C NMR (chloroform, 23 °C) δ (126 MHz, ppm): 203.7 (CO), 192.7 (C-9), 182.7 (C-10), 163.3 (C-2′), 163.2 (C-1), 162.9 (C-4′), 161.9 (C-8), 159.3 (C-6′), 152.4 (C-3), 137.1 (C-6), 134.4 (C-5a), 132.9 (C-4a), 125.8 (C-4), 125.0 (C-2), 123.9 (C-7), 120.1 (C-5), 115.4 (C-8a), 115.3 (C-1a), 107.1 (C-1′), 106.2 (C-3′), 90.5 (C-5′), 55.6 (C—OCH3), 33.1 (C—COCH3), 21.0 (C—CH3). IR: 3381 cm-1 (O—H), 2921 cm-1 (C—H), 1599 cm-1 (C=C), Mp 239–242 °C.

Experimental details

Absolute configuration was established by anomalous-dispersion effects in diffraction measurements {Flack parameter: 0.0(2)} on the crystal. Carbon-bound H atoms were placed in calculated positions and were included in the refinement in the riding model approximation, with Uiso(H) set to 1.2Ueq(C). The H atoms of the methyl groups were allowed to rotate with a fixed angle around the C—C bonds to best fit the experimental electron density (HFIX 137 in the SHELXL program [3]), with Uiso(H) set to 1.5Ueq(C). The H atoms of the hydroxyl groups were allowed to rotate with a fixed angle around the C—O bonds to best fit the experimental electron density (HFIX 147 in the SHELXL program [3]), with Uiso(H) set to 1.5Ueq(O).

Comment

The genus Bulbine Wolf (family Xanthorrhoeaceae and subfamily Asphodeloideae) comprises approximately 80 species mainly confined to southern Africa and Australia [8], [9]. In South Africa, the species have a centre of diversity in the Greater Cape Region where some of the 46 southern Africa species occur including B. latifolia [10]. B. latifolia (B. natalensis) known as rooiwortel (Afrikaans), ibhucu (Zulu) and ingcwelwane (isiXhosa) is a frost- tender evergreen plant with a rosette of fleshy, thornless, yellow-green leaves and is well distributed in the Eastern and Northern parts of South Africa as well as in other parts of Africa such as Malawi, Zimbabwe and Mozambique [11]. The roots have been used to ease vomiting and diarrhoea and also to treat convulsions, venereal disease, diabetes, rheumatism, urinary complaints and blood disorders [12].

Previous phytochemical investigations of this plant resulted in isolation of anthraquinones and phytosterols [13], [14]. In the present study, isolation of knipholone from the tubers of B. latifolia and the crystal structure of the compound are reported. Knipholone is the common name for 1-(3- acetyl-2,6-dihydroxy-4-methoxyphenyl)-4,5-dihydroxy-2-methylanthraquinone and has been reported as a marker for the bulbine species. But, the detailed crystal data of knipholone has not been reported previously. We have successfully obtained single crystals of knipholone and its structure was unambiguously determined.

The asymmetric unit cell contains four molecules of knipholone with all bond lengths and angles in expected ranges and similar to those of a related compound [15]. Although knipholone does not contain a chiral center, it is chiral due to restricted rotation about the biaryl axis. All four molecules in the asymmetric unit cell have the same stereochemistry corresponding to the (P)-1 stereostructure [10]. Each molecule has a slightly different conformation with the smallest and largest RMSD between two molecules being 0.2339 and 0.6266 respectively. One of the molecules has an dihedral angle of 67.92(9)° between the least square planes formed by the anthraquinone group and the phenyl ring. The dihedral angles for the remaining three molecules are almost orthogonal varying from 88.05(7) to 89.41(8)°. The RMS deviation of the least square plane through the anthraquinone group also shows large variation from 0.030 to 0.288.

Extensive intra and inter-molecular hydrogen bonding of the type O—H⋯O occurs. All the hydroxyl groups on the 1,8-dihydroxyanthraquinone groups have an interaction with the nearby carbonyl oxygen with a graph set descriptor [16] of S1,1(6). Similarly there is the same S1,1(6) interaction between a hydroxyl and acetyl group on the phenyl rings of all four knipholone molecules. For three of the knipholone molecules the remaining phenyl hydroxyl groups are involved in inter-molecular interactions. On one of the molecules the remaining phenyl hydroxyl has an intra-molecular interaction with a carbonyl oxygen on its anthraquinone group with graph set descriptor of S1,1(8) and bond length 2.879(4) Å. This enhances the distortion of the anthraquinone group which has the largest planar RMSD of all four molecules. There are three sets of intermolecular hydrogen bond interactions with graph set descriptors of C1,1(8) linking adjacent molecules in infinite chains. Two adjacent dihydroxyanthraquone groups interact to form a ring structure with a R2,2(16) descriptor. In addition there are four discrete intermolecular interaction patterns with D3,3 descriptors and atom numbers of 23, 25, 21 and 26.

Acknowledgements

We acknowledge Dr. P. Steyn and Prof. E. Campbell at Nelson Mandela University Herbarium for assistance in authentication of the plant species. This work was funded by the National Research Foundation (Thuthuka grant) under grant [number 113438] and Nelson Mandela University through the Postgraduate Research Scholarship (PGRS).

References

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Received: 2020-04-08
Accepted: 2020-05-17
Published Online: 2020-06-01
Published in Print: 2020-08-26

©2020 Buyiswa G. Hlangothi et al., published by De Gruyter, Berlin/Boston

This work is licensed under the Creative Commons Attribution 4.0 International License.

Articles in the same Issue

  1. Frontmatter
  2. Crystal structure of isopimara-7,15-dien-3-one, C20H30O
  3. Crystal structure of bis(6-aminopyridine-2-carboxylato-κ2O,N)-copper(II), C12H10O6N4Cu
  4. Crystal structure of 5,6-diphenyldibenzo[c, g]chrysene, C38H24
  5. Poly[bis(dimethylformamide-κO)-(μ8-5,5′′-dicarboxy-[1,1′:4′,1′′-terphenyl]-2′,3,3′′,5′-tetracarboxylato-κ8O:O1:O2:O3:O4:O5:O6:O7)dizinc(II)] — dimethylformamide (1/2), C18H19N2O8Zn
  6. The crystal structure of poly[bis(N,N-dimethylformamide-κ1O)(μ4- 2′,5,5′,5′′-tetracarboxy-[1,1′:4′,1′′-terphenyl]-3,3′′-dicarboxylato-κ4O:O′:O′′:O′′′)manganese(II)] — N,N-dimethylformamide (1/2), C36H40N4O16Mn
  7. Crystal structure of N,N-dimethyl-4-((7-nitrobenzo[c][1,2,5]thiadiazol-4-yl)ethynyl)aniline, C16H12N4O2S
  8. The crystal structure of 8a-methoxy 8a-methoxy-1,5,8a,9a-tetrahydro-4H-8,9-dioxa-3a1λ4-aza-8aλ4, C18H14BNO3
  9. Crystal structure of poly[diaqua-(μ2-5-isopropoxyisophthalato-κ2O:O′)-(μ2-(1,3-bis(3,5-di(1H-imidazol-1-yl)pyridine))-κ2N:N′)cobalt(II)] monohydrate, C22H25N5O8Co
  10. The crystal structure of acetoximium 1′-hydroxy-1H,1H′-5,5′-bitetrazole-1-olate monohydrate, C5H11N9O4
  11. Crystal structure of 3-(2-ethoxy-2-oxoethyl)-1-vinyl-1H-imidazol-3-ium hexafluoridophosphate(V), C9H13F6N2O2P
  12. The crystal structure of catena-poly[(μ2-4-(benzo[d]imidazol-2-yl)benzenecarboxylato-κ2N,O)-(μ2-4-(benzo[d]imidazol-2-yl)benzenecarboxylato-κ3N,O:O′)cadmium(II)]dihydrate, C28H22CdN4O6
  13. Enzyme-mediated synthesis and crystal structure of (2R,4S)-hydroxyketamine, C13H16ClNO2
  14. The crystal structure of bis(isothiocyanato-κ1N)-(methanol-κ1O)-[2-morpholine-4-yl-4,6-di(pyrazol-1-yl)-1,3,5-triazine-κ3N,N′,N′′] manganese(II), C16H18MnN10O2S2
  15. Crystal structure of bis{5-chloro-2-(((4-trifluoromethyl)imino)methyl)phenolato-κ2N,O}copper(II), C28H16Cl2CuF6N2O2
  16. Crystal structure of bis(1,3-phenylenedimethanaminium) bis(triiodide) tetraiodide – water (1/2) , C8H16I5N2O
  17. Crystal structure and anti-inflammatory activity of (3E,5E)-3,5-bis(2-fluorobenzylidene)-1-((4-fluorophenyl)sulfonyl)piperidin-4-one, C25H18F3NO3S
  18. The crystal structure of bis{3-(diphenylphosphaneyl)propanoato-κ2O,P}platinum(II) dihydrate, C30H28O6P2Pt
  19. The crystal structure of (E)-2-(4-((4-fluorobenzyl)oxy)styryl)-4,6-dimethoxybenzaldehyde, C24H21FO4
  20. Crystal structure of bis[3-methoxy-N-(1-(pyrazin-2-yl)ethylidene)benzohydrazonato-κ3O,N,N′]nickel(II), C28H26N8O4Ni
  21. Crystal structure of 1-(2-(pyridin-2-yl)-5-(pyridin-3-yl)-1,3,4-oxadiazol-3(2H)-yl)ethan-1-one, C14H12N4O2
  22. Synthesis and crystal structure of 3-N-acetyl-5-(pyridin-3-yl)-2-(quinolin-2-yl)-1,3,4-oxadiazoline, C18H14N4O2
  23. Crystal structure of 2-methyl-1H-perimidine, C12H10N2
  24. Crystal structure of (E)-2-(5,5-dimethyl-3-(4-((7-nitrobenzo[c][1,2,5]oxadiazol-4-yl)oxy)styryl)cyclohex-2-en-1-ylidene)malononitrile, C25H19N5O4
  25. Structural elucidation of 1-(3-acetyl-2,6-dihydroxy-4-methoxyphenyl)-4,5-dihydroxy-2-methylanthracene-9,10-dione isolated from Bulbine latifolia (L.) Wild, C24H18O8
  26. Crystal structure of 3-cinnamoyl-4-hydroxybenzoic acid, C16H12O4
  27. The crystal structure of poly[bis(μ4-2,3-pyridinedicarboxylato)-(μ2-oxalyl dihydrazide)-dicadmium(II) dihydrate], C16H16O12N6Cd2
  28. Synthesis and crystal structure of 1-{4-[(3-bromo-2-hydroxy-benzylidene)amino]phenyl}ethanone, C15H12BrNO2
  29. Synthesis and crystal structure of 1-{4-[(2-bromo-6-hydroxy-benzylidene)amino]phenyl}ethanone, C15H12BrNO2
  30. Crystal structure of (4-aminobenzoato-κ2O,O′)-[5,5,7,12,12,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane-κ4N,N′,N′′,N′′′]nickel(II) perchlorate monohydrate, C23H44ClN5NiO7
  31. Crystal structure of 1-{4-[(4-fluoro-2-hydroxy-benzylidene)amino]phenyl}ethanone, C15H12FNO2
  32. Preparation and crystal structure of a non-symmetrical vanadium(II) dimer: tri-μ2-bromido-(hydrogen-tris(3-isopropyl-4-bromopyrazol-1-yl)borato-κ3N,N′,N′′)-tris(tetrahydrofuran-κO)divanadium(II) – tetrahydrofuran (1/1), C34H57BBr6N6O4V2
  33. Crystal structure of bis{2-(((4-(1-(hydroxyl-imino)ethyl)phenyl)imino)methyl)phenolato-κ2N,O}cobalt(II), C30H26CoN4O4
  34. Crystal structure of 3-((3-nitrophenyl)sulfonamido)propanoic acid — 4,4′-bipyridine (1/1), C19H18N4O6S
  35. Crystal structure of cyclo[diaqua-bis(μ2-3′,5-dicarboxy-[1,1′-biphenyl]-3,4′-dicarboxylato-κ4O,O′:O′′,O′′′)-bis(4,4′-bis(pyrid-4-yl)biphenyl-K1N)dicadmium(II)], C76H52Cd2N4O18
  36. Crystal structure of 1-(adamantan-1-yl)-3-aminothiourea, C11H19N3S
  37. Crystal structure of catena-poly[triaqua-(μ2-1,4-di(pyridin-4-yl)benzene-κ2N:N′)-(3′,5-dicarboxy-[1,1′-biphenyl]-3,4′-dicarboxylato-κO)nickel(II)], C32H26N2O11Ni
  38. Crystal structure of catena-poly[aqua-(μ4-4,4′-(pyridine-3,5-diyl)dibenzoato-κ4O,O′:O′′:O′′′)zinc(II)], C19H13NO5Zn
  39. Crystal structure of 4-(4′-(pyridin-4-yl)-[1,1′-biphenyl]-4-yl)pyridin-1-ium 2-carboxy-4-(3,5-dicarboxyphenoxy)benzoate hydrate, C38H28N2O10
  40. Crystal structure of 3-[(triisopropylsilanyl)-ethynyl]-6a,12a-dihydro-1H-1,4-diaza-benzo[α]anthracene-2,7,12-trione, C27H28N2O3Si
  41. Crystal structure of [(bis(1,10-phenanthroline-κ2N,N′)-(2-carboxy-4-(3-carboxy-5-carboxylatophenoxy)benzoato-κ2O:O′))nickel(II) monohydrate, (1,10-phenanthroline-κ2N:N′)-(μ2-(5-(3′,4′-dicarboxylphenoxy)-isophthalate-κ2O:O′))nickel(II)], C40H24N4O9Ni ⋅ H2O
  42. Crystal structure of 4-(3-(pyridin-3-yl)ureido)benzoic acid — adipic acid (2/1), C16H16N3O5
  43. Crystal structure of poly[bis{μ2-5-carboxy-4′-methyl-[1,1′-biphenyl]-3-carboxylato-κ2O:O′}-{μ2-4,4′-bipyridine-κ2N:N′}]cobalt(II), C40H30N2O8Co
  44. Crystal structure of aqua-(2,2′-bipyridine-κ2N,N′)(((3-nitrophenyl)sulfonyl)glycine-κ2N,O)copper(II) dihydrate, C18H20CuN4O9S
  45. Crystal structure of bis{2-bromo-6-(((4-(1-(methoxyimino)ethyl)phenyl)imino)methyl)phenolato-κ2N,O}copper(II), C32H28Br2CuN4O4
  46. Crystal structure of bis(2-(2-((2,6-dichlorophenyl)amino)phenyl)acetato-κ2O,O′)-(1,10-phenanthroline-κ2N,N′)zinc(II), C40H28Cl4N4O4Zn
  47. Crystal structure of 2-(3,6-dimethyl-2,3-dihydro-4H-benzo[b][1,4]oxazin-4-yl)-2-oxoethyl acetate, C14H17NO4
  48. Crystal structure of poly[dibromido-bis(μ2-1,6-di(1H-imidazol-1-yl)hexane-κ2N:N′)cadmium(II)], C24H36Br2N8Cd
  49. Synthesis and crystal structure of ((6R,7S)-3-ethyl-6-phenyl-6,7-dihydro-5H-[1,2,4]triazolo[3,4-b][1,3,4]thiadiazin-7-yl)(phenyl)methanone hemihydrate, 2(C19H18N4OS) ⋅ H2O
  50. Crystal structure of 2-(5-(pyridin-3-yl)-4-(pyridin-4-yl)-4H-1,2,4-triazol-3-yl)pyridine, C17H12N6
  51. The crystal structure of N-((1E,2E)-1,3-bis(4-fluorophenyl)but-2-en-1-ylidene)-4-methylbenzenesulfonamide, C23H19F2NO2S
  52. Crystal structure of diacetato-κ1O-diethanol-κ1O-bis(μ2-2-(((2-hydroxyethyl)imino)methyl)-5-methoxyphenolato-κ4O,N,O′:O′′)dinickel(II), C28H42Ni2N2O12
  53. The crystal structure of catena-poly[chlorido-(μ2-1,4-bis(pyridin-3-yl-methoxy)benzene-κ2N:N′)copper(II)], C18H16ClN2O2Cu
  54. N′,N′′′-(((ethane-1,2-diylbis(oxy))bis(2,1-phenylene))bis(methaneylylidene))bis(2-hydroxybenzohydrazide)nickel(II), C30H24N4NiO6
  55. Crystal structure of (E)-3′,6′-bis(ethylamino)-2′,7′-dimethyl-2-(2-((quinolin-2-ylmethylene)amino)ethyl)spiro[isoindoline-1,9′-xanthen]-3-one, C38H37N5O2
  56. Crystal structure of 4,4′-di(1H-imidazol-1-yl)-1,1′-biphenyl-1-ium 5,3′,5′-tricarboxy-[1,10-biphenyl]-2-carboxylate, C25H17N2O8
  57. The crystal structure of 1-carboxy-2-(1H-indol-3-yl)-N,N,N-trimethylethan-1-ammonium chloride, C14H19N2O2Cl
  58. The crystal structure of 5-bromo-2-fluoronicotinic acid monohydrate, C6H5BrFNO3
  59. Crystal structure of ethyl 3-(trifluoromethyl)-1H-pyrazole-4-carboxylate, C7H7F3N2O2
  60. Crystal structure of tetrakis(1H-benzo[d]imidazol-3-ium) bis(μ5-phenylphosphonato)-pentakis(μ2-oxido)-decaoxo-penta-molybdenum dihydrate, C40H42Mo5N8O23P2
  61. Structure of 7-(3,3,4,4,5,5-hexafluoro-2-(2-methylbenzo[b]thiophen-3-yl)cyclopent-1-en-1-yl)-8-methylquinoline, C24H15F6NS
  62. Crystal structure of monocarbonyl[2-((cyclopentylmethylene)amino)-5-methylphenolato-κ2N,O] (tricyclohexylphosphine)rhodium(I), C32H48NO2PRh
  63. The crystal structure of fac-tricarbonyl(1,10-phenanthroline-κ2N,N′)-(pyrazole-κN)rhenium(I)nitrate, C18H12O3N4Re
  64. Crystal structure of poly[diaqua-bis(μ2-4-(3-(pyridin-3-yl)-1H-1,2,4-triazol-5-yl)benzoato-κ2N:O)nickel(II)], C28H22O6N8Ni
  65. Crystal structure of 4,4′-bis(pyridin-1-ium-4-yl)biphenyl poly[bis(μ2-4,4′-bis(pyrid-4-yl)biphenyl-K2N:N′)-tetrakis(μ4-4′-methyl-[1,1′-biphenyl]-3,5-dicarboxylato-K4O,O′:O′′:O′′′)-bis[[μ2-1,1′-biphenyl]-3-carboxyl-5-carboxylato-K2O:O′]tetracobalt(II)]— [1,1′-biphenyl]-3,5-dicarboxylic acid (1/2), C93H68N3O16Co2
  66. The crystal structure of 4a-formyl-1,2,3,4,4a,5,6,6a,6b,7,8,8a,9,10,11,12,12a,12b,13,14b-icosahydro-1-2-6a,6b,9,9,12a-heptamethylpicen-10-yl acetate, C32H50O3
  67. Crystal structure of 3,3′-(1,2-phenylenebis(methylene))bis(1-methyl-1H-imidazol-3-ium) bis(hexafluoridophosphate), C16H20F12N4P2
  68. Crystal structure of catena-poly[diaqua-(μ2-tartrato-κ4O,O′:O′′,O′′′)zinc(II)], C4H8O8Zn
  69. The crystal structure of (6aR,6bS,8aS,8bR,9S,11aS,12aS,12bS)-10-(4-acetoxy-3-methylbutyl)-6a,8a,9-trimethyl-3,4,5,6,6a,6b,7,8,8a,8b,9,10,11a,12,12a,12b-hexadecahydro-1H-naphtho[2′,1′:4,5]indeno[2,1-b]furan-4-yl acetate, C31H48O5
  70. Crystal structure of 4,4′-(oxybis(methylene))bis(bromobenzene), C14H12Br2O
  71. Crystal structure of (N,N-dimethylsulphoxide)-[N-(3-ethoxy-2-(oxide)benzylidene)-3-methoxybenzenecarbohydrazonato-κ3N,O,O′]-dioxo-molybdenum(VI), C19H22MoN2O7S
  72. Crystal structure of dichlorido-bis(dimethyl sulphoxide-κO)-bis(4-methylbenzyl-κC1)tin(IV), C20H30Cl2O2S2Sn
  73. Crystal structure of (E)-2-amino-N′-(2-hydroxy-4-(2-(piperidin-1-yl)ethoxy)benzylidene)benzohydrazide monohydrate, C21H26N4O3 ⋅ H2O
  74. Crystal structure of chloridotris(4-chlorophenyl)(dimethyl sulfoxide-κO)tin(IV), C20H18Cl4OSSn
  75. Crystal structure of catena{di-aqua-sodium-[N-(hydroxyethyl), N-isopropyl-dithiocarbamato]}n, [C6H16NNaO2S2]n
  76. Crystal structure of 2,2,4,4,6,6-hexakis(4-chlorophenyl)-1,3,5,2,4,6-trithiatristanninane, C36H24Cl6S3Sn3
  77. Crystal structure of 6-methoxy-3-(5-(3-methoxyphenyl)-1,3,4-oxadiazol-2-yl)-4H-chromen-4-one-methanol (1/1), C20H18N2O6
  78. Crystal structure of hexanedihydrazide, C6H14N4O2
  79. Crystal structure of tert-butyl 2-(hydroxymethyl)-5-{4-[(methoxycarbonyl)amino]phenyl}-2,5-dihydro-1H-pyrrole-1-carboxylate, C18H24N2O5
  80. Crystal structure of [(Z)-O-isopropyl N-(4-nitrophenyl)thiocarbamato-κS]-(triphenylphosphine-κP)-gold(I), C28H26AuN2O3PS
  81. Crystal structure of [O-ethyl N-(4-nitrophenyl)thiocarbamato-κS](tri-4-tolylphosphine-κP)gold(I) tetrahydrofuran solvate, C30H30AuN2O3PS, C4H8O
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