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51.
Vadithala Ramakrishna Rao Korandla Goverdhan Reddy Utukuri Venkata Seshaiah Vuppalapati Jayathyagaraju 《Transition Metal Chemistry》1993,18(3):258-261
Summary
N-salicylidene anthranilamide (H2SAA) and its CrIII, MnII, FeIII, CoII, NiII and CuII complexes were prepared and characterized by physicochemical and spectroscopic data. H2SAA enolizes to give a dibasic ONO donor set in the divalent metal complexes. It also binds to the trivalent metal ions in a nonenolized form using a monobasic ONN donor set. CoII is oxidized to CoIII during complexation. Octahedral geometries are proposed for CrIII, MnII, FeIII and CoIII complexes, while square planar geometries are suggested for the NiII and CuII complexes. Phenoxide bridging in the CrIII and FeIII complexes and enoxide bridging in the NiII and CuII complexes is proposed. 相似文献
52.
The total synthesis of the bioactive natural product (+)-Sch 642305 has been achieved from a readily available chiral building block using an RCM protocol to construct the key decalactone moiety; our approach is notable for its built-in flexibility and is diversity oriented. 相似文献
53.
Synthetic studies directed towards allo-cedrane based, tashironin sibling natural products, involving some deft functional group manipulations on a preformed tetracyclic scaffold, are delineated. 相似文献
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56.
A short synthesis of Hagen’s gland lactones 1 and 2 from commercially available pentanal and heptanal, respectively, is outlined. The approach relies on sequential ring closing metathesis and intramolecular oxy-Michael addition as the key transformations. 相似文献
57.
A short, flexible and enantioselective approach towards 10-membered germacratrienones, from the commercially available monoterpene chiron (−)-carvone, involving RCM and Grob-type fragmentation as the pivotal steps is delineated. 相似文献
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A new strategy toward the total synthesis of the novel structural complex and biologically potent neurotrophic factor merrilactone A from 2,3-dimethyl-2-cyclopentene-1,4-dione is outlined. The approach involving RCM and [2+2]-photocycloaddition as the key steps, is notable for the orchestration of a series of regio- and stereoselective operations that lead to the core structural motif present in the sesquiterpenoid natural product. 相似文献
60.
Goverdhan Mehta Saikat Sen Meenu Thangam 《Acta Crystallographica. Section C, Structural Chemistry》2011,67(8):o294-o296
The title compound, C14H18F2O2·0.5H2O, a hemihydrate of a Cs‐symmetric unsaturated difluorodiol, crystallizes in the centrosymmetric space group P2/m (Z = 4). The asymmetric unit contains two crystallographically independent difluorodiol half‐molecules, occupying the mirror planes at (x, 0, z) and (x, , z), and half a molecule of water, lying on the twofold axis at (0, y, 0). Four difluorodiol molecules self‐assemble around each solvent water molecule via O—H...O hydrogen bonds in a near tetrahedral symmetry to generate a cylindrical column‐like architecture. 相似文献