The reaction of the cross-conjugated enediyne Me2C[double bond, length as m-dash]C(C[triple bond, length as m-dash]CSiMe3)2 () with B(C6F5)3 gives the unusual borabicyclo[4.3.0]nonadiene product . The reaction sequence is initiated by 1,1-carboboration and is suggested to take a short subsequent sequence involving borane induced H migration reactions from the geminal pair of methyl groups.

Significance The structure of life emerged from randomness. This is attributed to selection by molecular Darwinian evolution. study found that random templated ligation led the simultaneous elongation and sequence oligomers. Product strands showed highly structured motifs which inhibited self-folding built self-templating reaction networks. By reduction space, kinetics duplex formation increase...

this text carries out some ideas about exact and p− exact sequences of transformationsemigroups. some theorems like the short five lemma (lemma 1.3 and lemma 2.3) are valid here as inexact sequences of r − modules.

let $p$ be a prime number greater than three. in this paper, we prove the existence of a new family of homotopy elements in the stable homotopy groups of spheres $pi_{ast}(s)$ which is represented by $h_nh_mtilde{beta}_{s+2}in {rm ext}_a^{s+4, q[p^n+p^m+(s+2)p+(s+1)]+s}(mathbb{z}_p,mathbb{z}_p)$ up to nonzero scalar in the adams spectral sequence, where $ngeq m+2>5$, $0leq sext}_a^{s+2,q[(s+2)p...

bemisia tabaci (gennadius) (hemiptera: aleyrodidae), is one of the most important pest of vegetable and fruit crops. this polyphagous pest has a range of natural enemies including the parasitoid eretmocerus mundus (merect) (hymenoptera: aphelinidae). to determine the molecular profile and taxonomic status of iranian isolates of e. mundus, parasitized b. tabaci samples were collected from cotton...

Abstract Al-Ti-B master alloy is currently the most widely used grain refiner in aluminum alloys. Reaction controlling plays an important role changing microstructure and improving refining effect. In this paper, prepared by fluoride salt method, control of in-situ generated phases realized establishing a thermodynamic analysis modelling. Results show that reactant change caused difference syst...

Ribonuclease A and ribonuclease S-protein have been investigated for their ability to catalyze the preparative synthesis of dinucleoside monophosphates and trinucleoside diphosphates of specific base composition and sequence. Kinetic analysis of identical reactions catalyzed by ribonuclease A and S-protein suggests that the synthetic activity of the native protein and the derivative differ with...

A short reaction sequence leads to oligoarene derivatives utilising a regioselective Scholl reaction for the unprecedented cyclisation to the mono-functionalised oligoarene under methanol elimination. Quantum-chemical investigations reveal the reason for the remarkably high regioselectivity.

ticks are important acarina that infest animals. they are obligatory blood sucker arthropods which economically impact cattle industry by reducing weight gain and production. moreover, they are important vectors of viral, bacterial, rickettsial and parasitic pathogens infecting humans and animals. in view of the importance of hyalomma anatolicum anatolicum in pathogen transmission, including th...