Chauliops fallax Scott, 1874 (Hemiptera: Heteroptera: Malcidae: Chauliopinae) is one of the most destructive insect pests of soybean and rice fields in Asia. Here we sequenced the complete mitochondrial genome of this pest. This genome is 15,739 bp long, with an A+T content of 73.7%, containing 37 typical animal mitochondrial genes and a control region. All genes were arranged in the same order as most of other Heteroptera. A remarkable strand bias was found for all nine protein coding genes (PCGs) encoded by the majority strand were positive AT-skew and negative GC-skew, whereas the reverse were found in the remaining four PCGs encoded by the minority strand and two rRNA genes. The models of secondary structures for the two rRNA genes of sequenced true bugs and Lygaeoidea were predicted. 16S rRNA consisted of six domains (domain III is absent as in other known arthropod mitochondrial genomes) and 45 helices, while three domains and 27 helices for 12S rRNA. The control region consists of five subregions: a microsatellite-like region, a tandem repeats region and other three motifs. The unusual intergenic spacer between tRNA-H and ND4 only found in the species of Lygaeoidea, not in other heteropteran species, may be the synapomorphy of this superfamily. Phylogenetic analyses were carried out based on all the 13 PCGs showed that Chauliopinae was the sister group of Malcinae and the monophyly of Lygaeoidea.
Pentatomomorpha is one of the most diversified infraorders of the true bugs (Insecta: Hemiptera: Heteroptera). The phylogenetic relationships among superfamilies within this infraorder are still in dispute. In this study, 31 species representing 26 pentatomomorphan and four cimicomorphan putative families were chosen, and six Hox gene fragments with as many as 4 kilobases for each representative were analyzed to reconstruct the phylogeny of the Pentatomomorpha. The (Homeotic) Hox gene family is a group of nuclear genes, which is considered to determine animal segmentation. The combined nucleotide and amino acid sequences were used separately as two data matrices, and analyzed by employing maximum likelihood and Bayesian methods. Results strongly support the monophyly of Trichophora and the superfamilies Pentatomoidea, Lygaeoidea, Coreoidea, and Pyrrhocoroidea. The relationship of (Aradoidea + (Pentatomoidea + (Lygaeoidea + (Coreoidea + Pyrrhocoroidea)))) was mostly congruent with previous results based on the morphological data. Our results suggested that the Hox genes could be used as novel molecular markers for phylogenetic research on the Pentatomomorpha and other insects.
An environmentally benign protocol that affords propargylic sulfones containing highly congested carbon centers from easily accessible alcohols and sulfinic acids with water as the only byproduct is reported. The reaction proceeded via an in situ dehydrative cross-coupling process by taking advantage of the synergetic actions of multiple hydrogen bonds rather than relying on an external catalyst and/or additives to achieve high product distribution.
A reciprocal-activation
strategy for allylic sulfination with unactivated
allylic alcohols was developed. In this reaction, the hydrogen bond
interaction between allylic alcohols and sulfinic acids allowed for
reciprocal activation, which enabled a dehydrative cross-coupling
process to occur under mild reaction conditions. This reaction worked
in an environmentally friendly manner, yielding water as the only
byproduct. A variety of allylic sulfones could be obtained in good
to excellent yields with wide functional group tolerance. In gram
scale reactions, allylic sulfones could be conveniently isolated in
high yield by filtration.
A Ba/Pd cooperative catalysis system was developed to enable the dehydrative cross-coupling of allylic alcohols with P-ylides to occur directly and promote a subsequent Wittig reaction in one pot. A variety of multisubstituted 1,4-dienes were isolated in good to excellent yields with broad P-ylides (stabilized by both ester and ketone carbonyl groups) and aldehyde (aliphatic and aromatic) substrates with excellent E selectivity.
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