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1.
Gowravaram Sabitha Narjis Fatima Peddabuddi Gopal C. Nagendra Reddy Jhillu S. Yadav 《Tetrahedron: Asymmetry》2009,20(2):184-191
Prins and olefin cross-metathesis reactions were used as the key steps for the stereoselective total synthesis of (+)-strictifolione and (6R)-6-[(4R,6R)-4,6-dihydroxy-10-phenyldec-1-enyl]-5,6-dihydro-2H-pyran-2-one. Removal of MOM protecting groups under neutral conditions using CeCl3·7H2O is an attractive addition to the present strategy. 相似文献
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Biswanath Das Boyapati Veeranjaneyulu Penagaluri Balasubramanyam Malampati Srilatha 《Tetrahedron: Asymmetry》2010,21(23):2762-2767
The stereoselective total synthesis of two naturally occurring α-pyrone derivatives, (+)-strictifolione and (6R)-6[(E,4R,6R)-4,6-dihydroxy-10-phenyl-1-decanyl]-5,6-dihydro-2H-2-pyrone has been accomplished involving the Sharpless kinetic resolution and olefin cross-metathesis as the key reactions. 相似文献
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A stereoselective total synthesis of (6R)-6-[(4R,6R)-4,6-dihydroxy-10-phenyldec-1-enyl]-5,6-dihydro-2H-pyran-2-one is reported. The strategy utilizes an iterative Jacobsen hydrolytic kinetic resolution, ring opening with a chiral propargylic synthon and a preferential (Z)-Wittig olefination reaction and lactonization as the key steps. 相似文献
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《Tetrahedron: Asymmetry》2007,18(18):2197-2200
A stereoselective synthesis of (6S)-5,6-dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one is reported. The strategy utilizes an olefin cross-metathesis, syn-benzylidene acetal formation and a preferential (Z)-Wittig olefination reaction and lactonization as the key steps. 相似文献
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An organocatalytic enantioselective synthesis of the title compounds has been achieved. The stereogenic centers were generated by the iterative use of proline catalyzed α-aminoxylations and HWE olefination of aldehydes while the lactone ring was constructed by ring closing metathesis. 相似文献
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The first efficient total syntheses of rugulactone and 6(R)-(4′-oxopent-2′-enyl)-5,6-dihydro-2H-pyran-2-one have been achieved in six steps with 51% and 48% overall yield, respectively. The key steps are Jacobsen’s hydrolytic kinetic resolution (HKR), Horner-Wadsworth-Emmons (HWE) homologation, and ring-closing metathesis reaction. 相似文献
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A chemoenzymatic synthesis of an enantiopure 6-substituted 5,6-dihydro-2H-pyran-2-one using bromobenzene as a starting material is presented. This important structural motif is found in a large number of chiral lactones that present a wide range of biological activities. The key features of the preparation include enzymatic dioxygenation of bromobenzene using Escherichia coli JM109 (pDTG601), microwave-assisted acyloin cleavage, and tin mediated lactonization. The stereochemical assignment for the alcohol was confirmed by NMR analysis of Moshe?s derivatives. 相似文献
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S. Chandrasekhar Ch. Narsihmulu S. Shameem Sultana M. Srinivasa Reddy 《Tetrahedron letters》2004,45(50):9299-9301
Iterative asymmetric allylations and ring-closing metathesis have been effectively performed for the first stereoselective total synthesis of (6S)-5,6-dihydro-6-[(2R)-2-hydroxy-6-phenylhexyl]-2H-pyran-2-one, a novel α,β-unsaturated-δ-lactone having antifungal activity, isolated from Ravensara crassifolia. 相似文献
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I. V. Mineeva 《Russian Journal of Organic Chemistry》2013,49(5):712-716
A simple and efficient asymmetric synthesis was performed of (+)-(S)-7,8-dihydrokanian and (4R,6R)-4-hydroxy-6-(2-phenylethyl)tetrahydro-2H-pyran-2-one involving Keck allylation in the key stage of building up the carbon scaffold of the target molecules. 相似文献
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The title compound was prepared by the condensation of 4,6-diphenyl-2H-pyran-2-one and acetophenone in phosphorus oxychloride. The absorption spectrum of this 2,2-methine dye is compared with those of the corresponding 2,4- and 4,4-methine dyes. 相似文献
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采用5,6-二氢-6-烷基(芳基)-2H-吡喃-2,4-二酮和醛进行缩合反应,合成了二[4-羟基-5,6-二氢-6-烷基(芳基)-2H-吡喃-2-酮-3-]烃.其结构经1HNMR和元素分析证实.对反应条件(反应温度、反应时间)进行了探讨.生物活性初步测定表明,该类化合物具有一定的杀菌和抗烟草花叶病毒的活性. 相似文献
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Matthew R. Aronoff 《Tetrahedron letters》2010,51(49):6375-6377
The first asymmetric total syntheses of the antiviral natural products (+)-sattabacin and (+)-4-hydroxysattabacin are reported. Both total syntheses are remarkably concise and were completed without the use of protecting groups. These syntheses allowed the unambiguous assignment of the absolute configuration of both natural products. The syntheses of these natural products, which exhibit marked antiviral activity, are readily amenable to the preparation of structural analogs and progress in this regard is also reported. 相似文献
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A practical synthesis of optically pure 1-[(3R,4R)-1-cyclooctylmethyl-3-ethoxycarbonyl-4-piperidinyl]-3-ethyl-1,3-dihydro-2H-benzimidazol-2-one (J-113397) was developed that avoids the use of chiral columns. 相似文献
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I. V. Mineeva 《Russian Journal of Organic Chemistry》2013,49(2):253-258
A simple and efficient asymmetrical synthesis was performed of a convenient bifunctional building block, methyl (R)-5,5-dimethoxy-3-methylpentanoate and its (S)-enantiomer. The possibility was shown of its application to the synthesis of insect pheromones. 相似文献