[reaction: see text] Four stereoisomers of the THF cores, synthetic intermediates of acetogenins, have been synthesized with high diastereoselectivity by asymmetric alkynylation and subsequent stereodivergent THF ring formation. The asymmetric alkynylation of alpha-oxyaldehyde with (S)-3-butyne-1,2-diol derivatives (C4-unit) gave good yields of syn and anti adducts with >97:3 dr and 94:6 dr, respectively. These adducts were converted into the four types of THF compounds via one-pot THF formation or via intramolecular Williamson synthesis.

All eight diastereoisomers of the monotetrahydrofuran-ring cores of annonaceous acetogenins have been synthesized through utilization of asymmetric alkynylation and stereodivergent one-pot tetrahydrofuran-ring formation. In all cases, the asymmetric alkynylation proceeded with very high diastereoselectivity to give eight kinds of optically pure tetrahydrofuran core from a common alpha-oxyaldehyde. We also describe a comparison of the (1)H NMR, (13)C NMR, and CD spectral data of the eight isomers and give full details of the tetrahydrofuran-ring construction including a model study of asymmetric alkynylation.

Formation. -(KOJIMA, N.; MAEZAKI*, N.; TOMINAGA, H.; ASAI, M.; YANAI, M.; TANAKA*, T.; Chem. Eur. J. 9 (2003) 20, 4980-4990; Grad. Sch. Pharm. Sci., Osaka Univ., Suita, Osaka 565, Japan; Eng.) -Adam 04-223

An intrinsically fluorescent cationic polyfluorene (CCP) has been designed, synthesized, characterized, and examined as a plasmid DNA (pDNA) delivery vector. This material facilitates nucleic acid binding, encapsulation and efficient cellular uptake. CCP can effectively protect pDNA against nuclease degradation, which is necessary for gene carriers. Green fluorescent protein (GFP) expression experiments reveal that CCP can achieve efficient delivery and transfection of pDNA encoding GFP gene with 92% efficiency, which surpasses that of commercial transfection agents, lipofectamine 2000 (Lipo) and polyethylenimine (PEI). CCP is also highly fluorescent, with 43% quantum yield in water, and exhibits excellent photostability, which allows for real‐time tracking the location of gene delivery and transfection. These features and capabilities represent a major step toward designing and applying conjugated polymers that function in both imaging and therapeutic applications.

Fused pyrrole derivativesFused pyrrole derivatives R 0160 Synthesis of Naphth[3,2,1-cd]indole by Heck Cyclization of 2-Methoxycarbonyl-3-benzoylindoles. -A second approach to the desired compound (VII) is also presented. It is noteworthy that the attempt to cyclize (VI) under radical reaction conditions fails. -(MIKI*, Y.; SHIROKOSHI, H.; ASAI, M.; AOKI, Y.; MATSUKIDA, H.; Heterocycles 60 (2003) 9, 2095-2101; Fac. Pharm. Sci.,