Naturally occurring styryl lactone, crassalactone D (1), unnatural 4-epi-crassalactone D (2), and the corresponding 7-epimers (3 and 4) have been synthesized starting from d-glucose. The key step of the synthesis is a new one-pot sequence that commenced with a Z-selective Wittig olefination of suitably functionalized sugar lactols with a stabilized ylide, (methoxycarbonylmethylene)-triphenylphosphorane, in dry methanol, to afford 1 or 3, in the mixtures with the corresponding 4-epimers (2 or 4, respectively). A number of 6-O-cinnamoyl derivatives of styryl lactones 1-4 have been prepared, bearing electron donating or electron withdrawing functionalities in the C-4 position of cinnamic acid residue.
View Article and Find Full Text PDFA series of new antitumour lactones containing the [3.3.0] bicyclic furano-lactone core and the halogen or azido group at the C-7 position have been designed, synthesized, and evaluated for their in vitro antitumour activity against a panel of human tumour cell lines.
View Article and Find Full Text PDFA new synthesis of goniobutenolides A (1) and B (2) and the corresponding 7-epimers has been achieved starting from diacetone d-glucose. The key step of the synthesis is a new one-pot sequence that commenced with Z-selective Wittig (or Horner-Wadsworth-Emmons) olefination, followed by successive γ-lactonisation and β-elimination. The above-mentioned unsaturated lactones were then converted to the corresponding 5-halogenated crassalactone D derivatives by using the appropriate haloetherification protocol.
View Article and Find Full Text PDFA series of styryl lactones containing the cinnamic acid ester groups such as (+)-crassalactones B (3a) and C (4a), 5,7-di-O-cinamoyl derivative 6, the corresponding 7-epimers and 7-deoxy derivatives have been synthesized, characterized and evaluated for their in vitro antitumour activity against a panel of several human tumour cell lines. Twelve new analogues such as 5-O- or 7-O-(4-methoxycinnamoyl), 5-O- or 7-O-(4-nitrocinnamoyl) and 5-O- or 7-O-(4-fluorocinnamoyl) esters of (+)-goniofufurone (3b-d), 7-epi-(+)-goniofufurone (epi-3b-d), as well as 7-deoxy derivatives 5b-d have been prepared to correlate all compounds in a SAR study. Some of the analogues displayed powerful antiproliferative effects on selected human tumour cell lines, but none of them demonstrated cytotoxicity towards the normal foetal lung fibroblasts (MRC-5).
View Article and Find Full Text PDFSynthesis of conformationally restricted (+)-goniofufurone (1) and 7-epi-(+)-goniofufurone (2) analogues, with embedded O-isopropylidene, O-methylidene or cyclic carbonate functions is disclosed starting from d-glucose. A number of potential bioisosteres of 1 and 2 bearing both 5,7-O-methylidene and 4-substituted cinnamoyloxy functions at the C-7 position have also been synthesized. In vitro cytotoxicity of target molecules against a number of human tumour cell lines were recorded and compared with those observed for the parent molecules 1 and 2.
View Article and Find Full Text PDFActa Crystallogr B Struct Sci Cryst Eng Mater
April 2013
Five new compounds belonging to the phosphoric triamide family have been synthesized: two of them with the formula XC(O)NHP(O)Y [X = CF3 (1) and CClF2 (2), Y = NHCH2C(CH3)2CH2NH] involving a 1,3-diazaphosphorinane ring part, and three 2,6-Cl2C6H3C(O)NHP(O)Z2 phosphoric triamides [Z = NHC(CH3)3 (3), N(CH3)(C6H11) (4) and N(CH3)(CH2C6H5) (5)]. The characterization was performed by (31)P{(1)H}, (1)H, (13)C NMR, IR spectroscopy besides (19)F NMR for fluorine containing compounds (1) and (2), and X-ray single-crystal structure analysis for (1), (3), (4) and (5). In each molecule the P atom has a distorted tetrahedral environment.
View Article and Find Full Text PDFThe title ferrocene-containing Mannich base, [Fe(C(5)H(5))(C(16)H(16)NO(2))], crystallizes with two independent mol-ecules (A and B) in the asymmetric unit. Mol-ecules A and B have similar conformations. The dihedral angles between the best planes of the benzene and substituted cyclo-penta-dienyl rings are 88.
View Article and Find Full Text PDFRecrystallization of the title compound, [Fe(C(5)H(5))(C(14)H(13)N(2)O(3))], from a mixture of n-hexane and dichloromethane gave the new polymorph, denoted (I), which crystallizes in the same space group (P1) as the previously reported structure, denoted (II). The Fe-C distances in (I) range from 2.015 (3) to 2.
View Article and Find Full Text PDFIndium promoted allylation of carbonyl compounds with 4-(bromomethyl)-1,3-dioxol-2-one diastereoselectively affords anti-α,β-dihydroxyketones, protected as enol carbonates. These initial products can be deprotected to free dihydroxyketones or transformed under mild conditions into the corresponding cyclic carbonates, which constitutes a useful approach to hydroxyacetone aldols.
View Article and Find Full Text PDFIn the new tin(IV) and copper(II) complexes, cis-dichlorido-trans-dimethyl-cis-bis(N,N',N''-tricyclohexylphosphoric triamide-κO)tin(IV), [Sn(CH(3))(2)Cl(2)(C(18)H(36)N(3)OP)(2)], (I), and trans-diaquabis(N,N',N''-tricyclohexylphosphoric triamide-κO)copper(II) dinitrate-N,N',N''-tricyclohexylphosphoric triamide (1/2), [Cu(C(18)H(36)N(3)OP)(2)(H(2)O)(2)](NO(3))(2)·2C(18)H(36)N(3)OP, (II), the N,N',N''-tricyclohexylphosphoric triamide (PTA) ligands exist as hydrogen-bonded dimers via P=O···H-N interactions around the metal center. The asymmetric unit in (I) consists of one complete complex molecule located on a general position. The Sn(IV) coordination geometry is octahedral with two cis hydrogen-bonded PTA ligands, two cis chloride ligands and two trans methyl groups.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
January 2011
In the title compound, C(16)H(16)Cl(4)N(3)O(2)P, the phosphoryl and carbonyl groups are anti to each other. The dihedral angle between the benzene rings is 33.59 (16)°.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
July 2010
The reaction of aqueous solutions of amino-guanidine hydrogennitrate and acetyl-acetone produces the title pyrazole salt, C(7)H(18)N(8) (2+)·2NO(3) (-). The crystal structure is stabilized by a complex N-H⋯O hydrogen-bonding network. The difference in the engagement of the two nitrate anions in hydrogen bonding is reflected in the variation of the corresponding N-O bond lengths.
View Article and Find Full Text PDFActa Crystallogr Sect E Struct Rep Online
January 2010
The P atom in the title compound, C(19)H(29)N(4)O(4)P, exhibits a tetra-hedral coordination and the phosphoryl and carbonyl groups are anti to each other. Adjacent mol-ecules are linked by N-H⋯O hydrogen bonds to form a layer motif.
View Article and Find Full Text PDFThe title compound, C(19)H(18)NO(3)P, was prepared by the reaction of diphenyl phospho-rochloridate and benzyl-amine. In the crystal structure, mol-ecules are linked via N-H⋯O=P hydrogen bonds into extended chains parallel to the c axis.
View Article and Find Full Text PDFA copper(II) complex with the pyridoxal-aminoguanidine (PL-AG) Schiff base adduct, as an organic compound of the very potent biological activity and promising pharmacological importance in the treatment of diabetic complications, has been prepared and characterized. The X-ray structural analysis of the [CuCl2(PL-AG)] complex showed that it has a distorted pseudo-square-pyramidal (4+1) structure with the tridentate ONN Schiff base in the equatorial plane, with the Cu-O(1), Cu-N(1) and Cu-N(3) bond lengths of 1.917(2)A, 1.
View Article and Find Full Text PDF