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3‐Deoxy‐3‐fluoro‐d ‐glucopyranose crystallizes from acetone to give a unit cell containing two crystallographically independent molecules. One of these molecules (at site A) is structurally homogeneous and corresponds to 3‐deoxy‐3‐fluoro‐β‐d ‐glucopyranose, C6H11FO5, (I). The second molecule (at site B) is structurally heterogeneous and corresponds to a mixture of (I) and 3‐deoxy‐3‐fluoro‐α‐d ‐glucopyranose, (II); treatment of the diffraction data using partial‐occupancy oxygen at the anomeric center gave a high‐quality packing model with an occupancy ratio of 0.84:0.16 for (II):(I) at site B. The mixture of α‐ and β‐anomers at site B appears to be accommodated in the lattice because hydrogen‐bonding partners are present to hydrogen bond to the anomeric OH group in either an axial or equatorial orientation. Cremer–Pople analysis of (I) and (II) shows the pyranosyl ring of (II) to be slightly more distorted than that of (I) [θ(I) = 3.85 (15)° and θ(II) = 6.35 (16)°], but the general direction of distortion is similar in both structures [ϕ(I) = 67 (2)° (BC1,C4) and ϕ(II) = 26.0 (15)° (C3TBC1); B = boat conformation and TB = twist‐boat conformation]. The exocyclic hydroxymethyl (–CH2OH) conformation is gg (gauchegauche) (H5 anti to O6) in both (I) and (II). Structural comparisons of (I) and (II) to related unsubstituted, deoxy and fluorine‐substituted monosaccharides show that the gluco ring can assume a wide range of distorted chair structures in the crystalline state depending on ring substitution patterns.  相似文献   

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The title mol­ecule, C26H30O3, shows a novel chemical rearrangement of the substituents at position 17, i.e. an α‐­orientation of the hydroxy group and a β‐orientation of the bulky benzyl moiety. The packing arrangement consists of coils formed by O2?O3 hydrogen bonds along the c axis. The compound shows complete loss of oestrogenic activity, and neither does it exhibit an antagonistic effect.  相似文献   

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Synthesis of Bis‐(2‐chloroethyl)amino‐substituted Diazaphosphorinones. Reversible Oxidative Addition of Hexafluoroacetone to σ3λ3‐Phosphorus Compounds. Synthesis of σ5λ5‐Spirophosphoranes and their Decomposition The reaction of 1‐methyl‐pyrido[3,2‐e]‐3,1‐oxazin‐2,4‐dione ( 1 ) with benzylamines led to the aminonicotinic acid amides 2 – 4 . Their reaction with phosphorus trichloride furnished the P‐chloro‐pyridodiazaphosphorinones 5 – 7 , which, upon reaction with bis‐(2‐chloroethyl) ammonium chloride/triethylamine, were converted into the P‐bis‐(2‐chloroethyl)amino‐substituted pyridodiazaphosphorinones 8 – 10 . The P‐chloro‐benzodiazaphosphorinone 11 was allowed to react with 2‐chloroethylammonium chloride/triethylamine to form the 2‐chloroethylamino‐substituted derivative 12 . The σ3‐diazaphosphorinones 8 , 9 , 12 and 13 were oxidized with the urea‐hydrogen peroxide‐(1 : 1)‐adduct to the corresponding phosphoryl derivatives 14 – 17 . The oxidative addition of hexafluoroacetone (HFA) to the σ3‐diazaphosphorinone 18 led, with abstraction of methyl chloride, to the tricyclic phosphorane 19 b . The spirophosphoranes 21 – 23 were formed by reaction of compounds 8 , 9 and 13 with HFA. NMR‐studies were made on the decomposition of the bicyclic phosphoranes 20 a , 22 and 23 . The oxidative addition of HFA to diazaphosphorinones was found to be reversible. Single crystal X‐ray determinations were conducted on compounds 17 and 19 b . They confirm the expected connectivity. Compound 17 was found to exhibit short C–H‥ O‐hydrogen bonds (H…O 234 pm). Compound 19 crystallises as two independent molecules which differ, e. g., in the orientation of the chloroethyl groups.  相似文献   

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The structures of methyl 3β‐acetoxy‐12‐oxo‐18β‐olean‐28‐oate [C33H52O5, (I)] and methyl 3β‐acetoxy‐12,19‐dioxoolean‐9(11),13(18)‐dien‐28‐oate [C33H46O6, (II)] are described. In (I), all rings are in the chair conformation, rings D and E are cis and the other rings trans‐fused. In compound (II), only rings A and E are in the chair conformation, ring B has a distorted chair conformation, ring C a distorted half‐boat and ring D an insignificantly distorted half‐chair conformation.  相似文献   

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The title compound, {[K(C5H9N2O7P2)(H2O)]·H2O}n, is polymeric and consists of layers parallel to (001) interconnected by hydrogen‐bonding and π–π interactions. The K+ cation is eightfold coordinated in a KO8 environment by O atoms from three different chelating zoledronate units and two coordinated water molecules. The zoledronate group presents its usual zwitterionic character, with negative charges in the singly protonated phosphonate groups and a positive charge at the protonated imidazole N atom. The anion binds to three different K+ cations in a (so far unreported) triply chelating manner. Intra‐ and interplanar interactions are enhanced by a variety of hydrogen bonds involving all available O—H and N—H donors. A strong imidazole–phosphonate C—H...O interaction is present in the structure.  相似文献   

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