Literature DB >> 21583658

3,28-Diacet-oxy-29-bromo-betulin.

Wei-Min Ding, Li-Jia Jing, Tao Yu, Yang Wang, Xiu-Feng Yan.   

Abstract

In the title mol-ecule, C(34)H(53)BrO(4), all the cyclo-hexane rings adopt chair conformations, while the cyclo-pentane ring adopts an envelope conformation. In the crystal, weak inter-molecular C-H⋯O hydrogen bonds link the mol-ecules into corrugated sheets parallel to the ab plane.

Entities:  

Year:  2009        PMID: 21583658      PMCID: PMC2977272          DOI: 10.1107/S1600536809027640

Source DB:  PubMed          Journal:  Acta Crystallogr Sect E Struct Rep Online        ISSN: 1600-5368


Related literature

For the anti-HIV and anti­tumor activities of betulin derivatives, see: Sun et al. (1998 ▶) and Kim et al. (1998 ▶), respectively. For a related structure, see Mohamed et al. (2006 ▶).

Experimental

Crystal data

C34H53BrO4 M = 605.67 Orthorhombic, a = 7.152 (3) Å b = 14.946 (7) Å c = 29.837 (12) Å V = 3189 (2) Å3 Z = 4 Mo Kα radiation μ = 1.32 mm−1 T = 291 K 0.40 × 0.38 × 0.37 mm

Data collection

Rigaku R-AXIS RAPID diffractometer Absorption correction: multi-scan (ABSCOR; Higashi, 1995 ▶) T min = 0.622, T max = 0.642 23319 measured reflections 5578 independent reflections 3534 reflections with I > 2σ(I) R int = 0.102

Refinement

R[F 2 > 2σ(F 2)] = 0.057 wR(F 2) = 0.145 S = 0.94 5578 reflections 358 parameters 18 restraints H-atom parameters constrained Δρmax = 0.45 e Å−3 Δρmin = −0.58 e Å−3 Absolute structure: Flack (1983 ▶), 2346 Friedel pairs Flack parameter: 0.024 (12) Data collection: RAPID-AUTO (Rigaku, 1998 ▶); cell refinement: RAPID-AUTO; data reduction: CrystalStructure (Rigaku/MSC, 2002 ▶); program(s) used to solve structure: SHELXS97 (Sheldrick, 2008 ▶); program(s) used to refine structure: SHELXL97 (Sheldrick, 2008 ▶); molecular graphics: SHELXTL (Sheldrick, 2008 ▶); software used to prepare material for publication: SHELXL97. Crystal structure: contains datablocks I, global. DOI: 10.1107/S1600536809027640/cv2584sup1.cif Structure factors: contains datablocks I. DOI: 10.1107/S1600536809027640/cv2584Isup2.hkl Additional supplementary materials: crystallographic information; 3D view; checkCIF report
C34H53BrO4F(000) = 1296
Mr = 605.67Dx = 1.261 Mg m3
Orthorhombic, P212121Mo Kα radiation, λ = 0.71073 Å
Hall symbol: P 2ac 2abCell parameters from 15343 reflections
a = 7.152 (3) Åθ = 3.1–27.4°
b = 14.946 (7) ŵ = 1.32 mm1
c = 29.837 (12) ÅT = 291 K
V = 3189 (2) Å3Block, colourless
Z = 40.40 × 0.38 × 0.37 mm
Rigaku R-AXIS RAPID diffractometer5578 independent reflections
Radiation source: fine-focus sealed tube3534 reflections with I > 2σ(I)
graphiteRint = 0.102
ω scansθmax = 25.0°, θmin = 3.1°
Absorption correction: multi-scan (ABSCOR; Higashi, 1995)h = −8→8
Tmin = 0.622, Tmax = 0.642k = −17→17
23319 measured reflectionsl = −35→35
Refinement on F2Secondary atom site location: difference Fourier map
Least-squares matrix: fullHydrogen site location: inferred from neighbouring sites
R[F2 > 2σ(F2)] = 0.057H-atom parameters constrained
wR(F2) = 0.145w = 1/[σ2(Fo2) + (0.066P)2] where P = (Fo2 + 2Fc2)/3
S = 0.94(Δ/σ)max < 0.001
5578 reflectionsΔρmax = 0.45 e Å3
358 parametersΔρmin = −0.58 e Å3
18 restraintsAbsolute structure: Flack (1983), 2346 Friedel pairs
Primary atom site location: structure-invariant direct methodsFlack parameter: 0.024 (12)
Geometry. All e.s.d.'s (except the e.s.d. in the dihedral angle between two l.s. planes) are estimated using the full covariance matrix. The cell e.s.d.'s are taken into account individually in the estimation of e.s.d.'s in distances, angles and torsion angles; correlations between e.s.d.'s in cell parameters are only used when they are defined by crystal symmetry. An approximate (isotropic) treatment of cell e.s.d.'s is used for estimating e.s.d.'s involving l.s. planes.
Refinement. Refinement of F2 against ALL reflections. The weighted R-factor wR and goodness of fit S are based on F2, conventional R-factors R are based on F, with F set to zero for negative F2. The threshold expression of F2 > σ(F2) is used only for calculating R-factors(gt) etc. and is not relevant to the choice of reflections for refinement. R-factors based on F2 are statistically about twice as large as those based on F, and R- factors based on ALL data will be even larger.
xyzUiso*/Ueq
Br11.44746 (8)−0.01367 (6)0.18762 (2)0.1130 (4)
C11.0979 (5)0.4597 (3)0.38899 (13)0.0394 (10)
H1A1.22510.44680.37980.047*
H1B1.02390.46850.36210.047*
C21.0967 (5)0.5466 (3)0.41652 (14)0.0419 (10)
H2A1.17800.54010.44230.050*
H2B1.14370.59550.39840.050*
C30.9011 (6)0.5672 (3)0.43183 (13)0.0384 (10)
H30.82150.57440.40530.046*
C40.8156 (5)0.4940 (3)0.46193 (12)0.0366 (9)
C50.8272 (5)0.4054 (3)0.43421 (12)0.0311 (9)
H50.74950.41690.40780.037*
C60.7341 (6)0.3239 (3)0.45702 (14)0.0430 (11)
H6A0.81620.30060.48010.052*
H6B0.61820.34240.47120.052*
C70.6935 (5)0.2506 (3)0.42254 (13)0.0380 (10)
H7A0.60440.27330.40080.046*
H7B0.63600.20020.43770.046*
C80.8677 (5)0.2177 (3)0.39760 (12)0.0308 (9)
C90.9820 (4)0.3005 (3)0.37983 (11)0.0294 (8)
H90.90090.32760.35710.035*
C101.0203 (4)0.3785 (3)0.41474 (11)0.0281 (8)
C111.1536 (5)0.2692 (3)0.35383 (13)0.0379 (10)
H11A1.23950.24040.37440.045*
H11B1.21640.32110.34130.045*
C121.1069 (5)0.2039 (3)0.31566 (13)0.0367 (9)
H12A1.03730.23540.29260.044*
H12B1.22230.18250.30240.044*
C130.9924 (5)0.1240 (3)0.33177 (12)0.0310 (9)
H131.06810.09340.35440.037*
C140.8095 (5)0.1562 (3)0.35600 (12)0.0324 (9)
C150.6922 (6)0.0744 (3)0.37207 (14)0.0445 (11)
H15A0.75190.04920.39840.053*
H15B0.56950.09550.38100.053*
C160.6672 (6)−0.0005 (3)0.33708 (15)0.0503 (11)
H16A0.6061−0.05120.35110.060*
H16B0.58650.02080.31320.060*
C170.8514 (6)−0.0310 (3)0.31707 (13)0.0423 (10)
C180.9435 (5)0.0536 (3)0.29593 (12)0.0341 (9)
H180.84720.08100.27700.041*
C191.0936 (5)0.0189 (3)0.26382 (12)0.0395 (9)
H191.20800.00730.28090.047*
C201.1404 (6)0.0818 (3)0.22529 (15)0.0500 (12)
C211.0121 (7)−0.0725 (3)0.24745 (15)0.0582 (13)
H21A0.9779−0.06880.21600.070*
H21B1.1044−0.11950.25090.070*
C220.8384 (7)−0.0930 (3)0.27615 (16)0.0549 (12)
H22A0.7249−0.08110.25940.066*
H22B0.8381−0.15520.28540.066*
C230.6078 (6)0.5185 (3)0.46879 (16)0.0609 (14)
H23A0.55250.47790.48990.091*
H23B0.54310.51440.44070.091*
H23C0.59870.57850.48010.091*
C240.9094 (6)0.4905 (3)0.50812 (12)0.0520 (11)
H24A1.04280.48910.50450.078*
H24B0.86930.43770.52370.078*
H24C0.87490.54260.52510.078*
C251.1663 (5)0.3518 (3)0.45069 (14)0.0448 (11)
H25A1.26270.31630.43710.067*
H25B1.10630.31770.47390.067*
H25C1.22050.40480.46340.067*
C260.9830 (6)0.1609 (3)0.43158 (12)0.0464 (11)
H26A0.97800.18850.46060.070*
H26B1.11060.15750.42180.070*
H26C0.93140.10170.43330.070*
C270.6862 (5)0.2109 (3)0.32242 (13)0.0416 (10)
H27A0.64940.17300.29800.062*
H27B0.75680.26060.31110.062*
H27C0.57680.23250.33760.062*
C280.9630 (7)−0.0780 (3)0.35488 (15)0.0532 (12)
H28A1.0021−0.03410.37690.064*
H28B0.8833−0.12130.36980.064*
C291.3386 (8)0.0938 (4)0.21333 (19)0.0841 (19)
H29A1.40840.11030.23990.101*
H29B1.34940.14240.19190.101*
C301.0135 (8)0.1247 (4)0.20139 (15)0.0696 (16)
H30A1.05040.16130.17780.084*
H30B0.88730.11840.20820.084*
C311.2306 (8)−0.1665 (4)0.3652 (2)0.0732 (16)
C321.3789 (7)−0.2221 (4)0.3428 (2)0.094 (2)
H32A1.4944−0.21610.35890.141*
H32B1.3957−0.20190.31260.141*
H32C1.3411−0.28370.34270.141*
C330.8263 (7)0.7245 (3)0.43739 (18)0.0534 (12)
C340.8185 (9)0.8011 (3)0.46859 (19)0.0819 (18)
H34A0.94130.82610.47190.123*
H34B0.77380.78120.49720.123*
H34C0.73540.84580.45690.123*
O11.1239 (5)−0.1224 (2)0.33705 (11)0.0625 (9)
O21.2042 (7)−0.1640 (4)0.40533 (18)0.1280 (19)
O30.8996 (4)0.65128 (19)0.45704 (10)0.0473 (7)
O40.7726 (6)0.7259 (2)0.39882 (13)0.0783 (11)
U11U22U33U12U13U23
Br10.0718 (4)0.1855 (9)0.0816 (4)0.0435 (5)0.0114 (3)−0.0252 (5)
C10.039 (2)0.044 (3)0.035 (2)−0.0083 (19)0.0101 (17)−0.0059 (19)
C20.047 (2)0.037 (3)0.042 (2)−0.010 (2)0.0035 (19)−0.0031 (19)
C30.050 (2)0.032 (2)0.033 (2)0.0026 (19)−0.0026 (18)−0.0114 (18)
C40.0410 (19)0.038 (2)0.0307 (19)0.001 (2)0.0084 (16)−0.0040 (19)
C50.0329 (19)0.032 (2)0.029 (2)−0.0004 (17)0.0074 (16)0.0006 (17)
C60.046 (2)0.042 (3)0.041 (2)−0.008 (2)0.0186 (19)−0.001 (2)
C70.044 (2)0.033 (2)0.038 (2)−0.0085 (19)0.0154 (18)0.0018 (19)
C80.0327 (18)0.031 (2)0.0285 (19)−0.0018 (17)0.0032 (16)0.0014 (17)
C90.0260 (17)0.036 (2)0.0257 (18)0.0005 (16)0.0028 (14)0.0018 (16)
C100.0263 (18)0.033 (2)0.0250 (18)−0.0032 (16)−0.0006 (15)0.0006 (17)
C110.0321 (19)0.038 (2)0.044 (2)−0.0041 (19)0.0077 (17)−0.0048 (19)
C120.0346 (19)0.034 (2)0.041 (2)−0.0028 (17)0.0098 (18)−0.0103 (19)
C130.0304 (18)0.031 (2)0.032 (2)0.0034 (16)−0.0028 (15)0.0021 (17)
C140.0334 (18)0.031 (2)0.032 (2)−0.0026 (18)0.0030 (16)−0.0023 (17)
C150.046 (2)0.039 (3)0.048 (3)−0.005 (2)0.013 (2)−0.006 (2)
C160.056 (2)0.037 (3)0.058 (3)−0.016 (2)0.008 (2)−0.008 (2)
C170.055 (2)0.031 (2)0.041 (2)−0.002 (2)0.0046 (19)−0.004 (2)
C180.0378 (18)0.034 (2)0.0303 (18)0.0008 (18)−0.0003 (16)−0.0001 (17)
C190.050 (2)0.037 (2)0.0312 (19)0.004 (2)0.0009 (16)−0.0066 (18)
C200.060 (3)0.049 (3)0.041 (2)−0.003 (2)0.010 (2)−0.012 (2)
C210.083 (3)0.045 (3)0.047 (3)−0.004 (3)0.009 (2)−0.012 (2)
C220.069 (3)0.038 (3)0.058 (3)−0.007 (2)0.001 (2)−0.007 (2)
C230.049 (2)0.052 (3)0.082 (3)−0.001 (2)0.024 (2)−0.021 (3)
C240.078 (3)0.049 (3)0.029 (2)−0.007 (3)0.0065 (19)−0.004 (2)
C250.042 (2)0.047 (3)0.045 (2)0.006 (2)−0.0109 (19)−0.005 (2)
C260.066 (3)0.041 (3)0.033 (2)0.001 (2)−0.008 (2)0.007 (2)
C270.0335 (19)0.051 (3)0.041 (2)0.0097 (19)−0.0099 (17)−0.004 (2)
C280.072 (3)0.036 (3)0.052 (3)0.003 (3)0.003 (2)0.007 (2)
C290.075 (3)0.115 (5)0.062 (3)−0.033 (4)0.011 (3)−0.009 (4)
C300.089 (4)0.078 (4)0.041 (3)0.016 (3)0.004 (3)0.008 (3)
C310.066 (3)0.074 (4)0.079 (4)−0.009 (3)−0.014 (3)0.001 (4)
C320.065 (3)0.064 (4)0.153 (6)0.014 (3)−0.022 (4)−0.005 (4)
C330.056 (3)0.040 (3)0.064 (3)−0.004 (2)0.006 (2)−0.006 (3)
C340.107 (4)0.046 (3)0.093 (4)−0.001 (3)0.018 (4)−0.025 (3)
O10.078 (2)0.054 (2)0.055 (2)0.0185 (19)−0.0040 (17)0.0052 (17)
O20.109 (3)0.179 (5)0.097 (3)0.039 (3)−0.026 (3)0.022 (3)
O30.0630 (18)0.0353 (18)0.0435 (16)0.0022 (15)−0.0035 (14)−0.0104 (14)
O40.108 (3)0.049 (2)0.078 (3)0.013 (2)−0.027 (2)0.005 (2)
Br1—C291.943 (6)C17—C281.550 (6)
C1—C21.537 (5)C17—C181.559 (5)
C1—C101.539 (5)C18—C191.530 (5)
C1—H1A0.9700C18—H180.9800
C1—H1B0.9700C19—C201.522 (6)
C2—C31.504 (6)C19—C211.563 (6)
C2—H2A0.9700C19—H190.9800
C2—H2B0.9700C20—C301.320 (6)
C3—O31.464 (5)C20—C291.473 (7)
C3—C41.542 (6)C21—C221.540 (7)
C3—H30.9800C21—H21A0.9700
C4—C241.534 (5)C21—H21B0.9700
C4—C231.544 (5)C22—H22A0.9700
C4—C51.563 (5)C22—H22B0.9700
C5—C61.546 (5)C23—H23A0.9600
C5—C101.551 (5)C23—H23B0.9600
C5—H50.9800C23—H23C0.9600
C6—C71.531 (6)C24—H24A0.9600
C6—H6A0.9700C24—H24B0.9600
C6—H6B0.9700C24—H24C0.9600
C7—C81.532 (5)C25—H25A0.9600
C7—H7A0.9700C25—H25B0.9600
C7—H7B0.9700C25—H25C0.9600
C8—C261.559 (5)C26—H26A0.9600
C8—C91.574 (5)C26—H26B0.9600
C8—C141.600 (5)C26—H26C0.9600
C9—C111.525 (5)C27—H27A0.9600
C9—C101.588 (5)C27—H27B0.9600
C9—H90.9800C27—H27C0.9600
C10—C251.550 (5)C28—O11.431 (5)
C11—C121.537 (5)C28—H28A0.9700
C11—H11A0.9700C28—H28B0.9700
C11—H11B0.9700C29—H29A0.9700
C12—C131.526 (5)C29—H29B0.9700
C12—H12A0.9700C30—H30A0.9300
C12—H12B0.9700C30—H30B0.9300
C13—C181.540 (5)C31—O21.211 (7)
C13—C141.570 (5)C31—O11.313 (6)
C13—H130.9800C31—C321.504 (8)
C14—C151.558 (5)C32—H32A0.9600
C14—C271.565 (5)C32—H32B0.9600
C15—C161.541 (5)C32—H32C0.9600
C15—H15A0.9700C33—O41.213 (6)
C15—H15B0.9700C33—O31.348 (6)
C16—C171.516 (6)C33—C341.477 (7)
C16—H16A0.9700C34—H34A0.9600
C16—H16B0.9700C34—H34B0.9600
C17—C221.536 (6)C34—H34C0.9600
C2—C1—C10113.4 (3)C16—C17—C28107.3 (4)
C2—C1—H1A108.9C22—C17—C28109.6 (4)
C10—C1—H1A108.9C16—C17—C18106.4 (3)
C2—C1—H1B108.9C22—C17—C18101.1 (3)
C10—C1—H1B108.9C28—C17—C18116.4 (3)
H1A—C1—H1B107.7C19—C18—C13120.5 (3)
C3—C2—C1109.9 (3)C19—C18—C17106.0 (3)
C3—C2—H2A109.7C13—C18—C17111.6 (3)
C1—C2—H2A109.7C19—C18—H18105.9
C3—C2—H2B109.7C13—C18—H18105.9
C1—C2—H2B109.7C17—C18—H18105.9
H2A—C2—H2B108.2C20—C19—C18114.7 (3)
O3—C3—C2109.8 (3)C20—C19—C21112.7 (3)
O3—C3—C4107.9 (3)C18—C19—C21103.3 (3)
C2—C3—C4113.6 (3)C20—C19—H19108.6
O3—C3—H3108.5C18—C19—H19108.6
C2—C3—H3108.5C21—C19—H19108.6
C4—C3—H3108.5C30—C20—C29118.1 (5)
C24—C4—C3112.0 (3)C30—C20—C19123.9 (4)
C24—C4—C23108.1 (3)C29—C20—C19118.0 (5)
C3—C4—C23106.9 (3)C22—C21—C19107.5 (4)
C24—C4—C5115.1 (3)C22—C21—H21A110.2
C3—C4—C5105.8 (3)C19—C21—H21A110.2
C23—C4—C5108.8 (3)C22—C21—H21B110.2
C6—C5—C10110.1 (3)C19—C21—H21B110.2
C6—C5—C4114.3 (3)H21A—C21—H21B108.5
C10—C5—C4117.7 (3)C17—C22—C21105.9 (4)
C6—C5—H5104.4C17—C22—H22A110.6
C10—C5—H5104.4C21—C22—H22A110.6
C4—C5—H5104.4C17—C22—H22B110.6
C7—C6—C5110.5 (3)C21—C22—H22B110.6
C7—C6—H6A109.6H22A—C22—H22B108.7
C5—C6—H6A109.6C4—C23—H23A109.5
C7—C6—H6B109.6C4—C23—H23B109.5
C5—C6—H6B109.6H23A—C23—H23B109.5
H6A—C6—H6B108.1C4—C23—H23C109.5
C6—C7—C8113.7 (3)H23A—C23—H23C109.5
C6—C7—H7A108.8H23B—C23—H23C109.5
C8—C7—H7A108.8C4—C24—H24A109.5
C6—C7—H7B108.8C4—C24—H24B109.5
C8—C7—H7B108.8H24A—C24—H24B109.5
H7A—C7—H7B107.7C4—C24—H24C109.5
C7—C8—C26106.8 (3)H24A—C24—H24C109.5
C7—C8—C9109.5 (3)H24B—C24—H24C109.5
C26—C8—C9111.9 (3)C10—C25—H25A109.5
C7—C8—C14110.5 (3)C10—C25—H25B109.5
C26—C8—C14109.2 (3)H25A—C25—H25B109.5
C9—C8—C14109.0 (3)C10—C25—H25C109.5
C11—C9—C8110.4 (3)H25A—C25—H25C109.5
C11—C9—C10114.8 (3)H25B—C25—H25C109.5
C8—C9—C10116.5 (3)C8—C26—H26A109.5
C11—C9—H9104.5C8—C26—H26B109.5
C8—C9—H9104.5H26A—C26—H26B109.5
C10—C9—H9104.5C8—C26—H26C109.5
C1—C10—C25107.8 (3)H26A—C26—H26C109.5
C1—C10—C5107.7 (3)H26B—C26—H26C109.5
C25—C10—C5114.1 (3)C14—C27—H27A109.5
C1—C10—C9108.3 (3)C14—C27—H27B109.5
C25—C10—C9112.4 (3)H27A—C27—H27B109.5
C5—C10—C9106.4 (3)C14—C27—H27C109.5
C9—C11—C12113.4 (3)H27A—C27—H27C109.5
C9—C11—H11A108.9H27B—C27—H27C109.5
C12—C11—H11A108.9O1—C28—C17110.7 (3)
C9—C11—H11B108.9O1—C28—H28A109.5
C12—C11—H11B108.9C17—C28—H28A109.5
H11A—C11—H11B107.7O1—C28—H28B109.5
C13—C12—C11112.4 (3)C17—C28—H28B109.5
C13—C12—H12A109.1H28A—C28—H28B108.1
C11—C12—H12A109.1C20—C29—Br1112.4 (4)
C13—C12—H12B109.1C20—C29—H29A109.1
C11—C12—H12B109.1Br1—C29—H29A109.1
H12A—C12—H12B107.9C20—C29—H29B109.1
C12—C13—C18116.0 (3)Br1—C29—H29B109.1
C12—C13—C14110.6 (3)H29A—C29—H29B107.9
C18—C13—C14109.9 (3)C20—C30—H30A120.0
C12—C13—H13106.6C20—C30—H30B120.0
C18—C13—H13106.6H30A—C30—H30B120.0
C14—C13—H13106.6O2—C31—O1121.8 (6)
C15—C14—C27107.6 (3)O2—C31—C32124.4 (6)
C15—C14—C13110.5 (3)O1—C31—C32113.7 (6)
C27—C14—C13109.6 (3)C31—C32—H32A109.5
C15—C14—C8110.6 (3)C31—C32—H32B109.5
C27—C14—C8110.1 (3)H32A—C32—H32B109.5
C13—C14—C8108.5 (3)C31—C32—H32C109.5
C16—C15—C14115.1 (3)H32A—C32—H32C109.5
C16—C15—H15A108.5H32B—C32—H32C109.5
C14—C15—H15A108.5O4—C33—O3123.4 (4)
C16—C15—H15B108.5O4—C33—C34124.9 (5)
C14—C15—H15B108.5O3—C33—C34111.7 (5)
H15A—C15—H15B107.5C33—C34—H34A109.5
C17—C16—C15112.6 (3)C33—C34—H34B109.5
C17—C16—H16A109.1H34A—C34—H34B109.5
C15—C16—H16A109.1C33—C34—H34C109.5
C17—C16—H16B109.1H34A—C34—H34C109.5
C15—C16—H16B109.1H34B—C34—H34C109.5
H16A—C16—H16B107.8C31—O1—C28117.5 (4)
C16—C17—C22116.2 (3)C33—O3—C3118.4 (3)
D—H···AD—HH···AD···AD—H···A
C32—H32A···O4i0.962.483.365 (7)154
C28—H28B···O4ii0.972.573.487 (6)158
Table 1

Hydrogen-bond geometry (Å, °)

D—H⋯AD—HH⋯ADAD—H⋯A
C32—H32A⋯O4i0.962.483.365 (7)154
C28—H28B⋯O4ii0.972.573.487 (6)158

Symmetry codes: (i) ; (ii) .

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