A general and convenient palladium-catalyzed oxidative Heck arylation of both N-protected and N,N-diprotected allylic amines with arylboronic acids under mild conditions has been developed. The catalyst system, consisting of PdA C H T U N G T R E N N U N G (OAc) 2 (palladium acetate), AgOAc (silver acetate) and KHF 2 (potassium hydrogen fluoride), could efficiently catalyze the coupling reaction in acetone without the aid of any ligand, leading exclusively to the g-arylated allylic amine products in good to excellent yields. This method is highlighted with excellent regio-and stereocontrol and remarkable functional group tolerance. The carbamate moiety in allylic amine substrates is of crucial importance to the catalytic performance, and the chelation between the carbonyl O (oxygen) and Pd (palladium) atoms is believed to be responsible for the high regioselectivity and stereoselectivity observed.

Begomovirus-DNA-␤ disease complexes induce different symptom phenotypes in their hosts. To investigate the genetic determinants of the phenotypic differences, Nicotiana spp. and tomato plants were inoculated with infectious clones of Tobacco curly shoot virus (TbCSV)/TbCSV DNA-␤ (TbCSB) and Tomato yellow leaf curl China virus (TYLCCNV)/TYLCCNV DNA-␤ (TYLCCNB) pseudorecombinants and showed that TYLCCNB induced characteristic vein-thickening and enation symptoms, while TbCSB only slightly exacerbated the leaf-curling symptoms, regardless of the helper virus being used. The roles of DNA-␤-encoded ␤C1 and a 430-nucleotide fragment containing the A-rich region and the putative ␤C1 promoter region of the ␤C1 gene (referred to as AP) in symptom development were further investigated by constructing hybrid satellites in which the ␤C1 coding region or AP was exchanged between the two satellite molecules. A TYLCCNB hybrid with TbCSB ␤C1 lost the ability to elicit the vein-thickening and enation phenotypes. TbCSB hybrids containing the TYLCCNB ␤C1 or AP fragment failed to induce the characteristic vein thickening and enations. A TYLCCNB hybrid having the TbCSB AP fragment produced the enations, but the number of enations was less and their sizes were reduced. Differently from the phloem-specific pattern of the TYLCCNB promoter, a full-length fragment upstream of the TbCSB ␤C1 gene confers a constitutive ␤-glucuronidase expression pattern in transgenic tobacco plants. The above results indicate that the DNA-␤-encoded ␤C1 protein is the symptom determinant, but the promoter of the ␤C1 gene has influence on symptom production.Geminiviruses are small plant viruses with circular singlestranded DNA (ssDNA) genomes that are encapsidated in unique twinned (geminate) particles. Members of the genus Begomovirus are transmitted by whiteflies (Bemisia tabaci) and infect dicotyledonous plants (42). Begomoviruses have either one or two circular ssDNA genomic components (DNA-A and DNA-B). The DNA-A component is capable of autonomous replication and encapsidation, whereas the DNA-B component encodes two proteins (BC1 and BV1) involved in movement (14). Recently, some monopartite begomoviruses have been found in association with a novel satellite DNA molecule, referred to as DNA-␤ and now known as a betasatellite (2,5,20,22,38,45). DNA-␤ is approximately half the size of the viral genomic DNA, and apart from a nonanucleotide sequence (TA ATATTAC), it has little sequence identity with viral genomic DNA. DNA-␤ depends on the helper virus for replication and encapsidation and, in turn, is required for the induction of bona fide disease symptoms. DNA-␤ bears a ␤C1 open reading frame (ORF) on the complementary-sense strand, which is conserved among distinct betasatellites in terms of position and size. Mutational analyses and constitutive expression have shown that ␤C1 is a strong pathogenicity/symptom determinant (7, 34, 39).Begomovirus-DNA-␤ disease complexes are associated with a wide range of plant species and induce different sets of sympto...

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Palladium-Catalyzed Regioselective and Stereoselective Oxidative Heck Arylation of Allylamines with Arylboronic Acids. -A general and convenient method for the oxidative Heck arylation of both N-mono-and N,N-diprotected allylic amines under mild conditions is developed. The method is highlighted by its excellent regioand stereoselectivity as well as its remarkable functional group tolerance. -(ZHANG, L.; DONG, C.; DING, C.; CHEN, J.; TANG, W.; LI, H.; XU*, L.; XIAO, J.; Adv. Synth. Catal. 355 (2013) 8, 1570-1578, http://dx.

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