Komplexchemie perhalogenierter Cyclopentadiene und Alkine, VII

Coordination Chemistry of Perhalogenated Cyclopentadienes and Alkynes, VII1). - Synthesis of Several Tetrachlorometalloles of Cobalt, Rhodium, and Iridium; Structure of a Iridacyclopentadiene Derivative The reaction of dichloroethyne with CpCo(PPh3)2, RhCl(EPh3)3 (E = P, As, Sb), and IrCl(N2)(PPh3)2 leads to the formation of complexes containing a tetrachloro-1-metallacyclopentadiene unit. The crystal-structure determination of (Ph3P)2(Cl)- is reported

Unprecedented spin localisation in a metal-metal bonded dirhenium complex

he molecular and electronic structure of edge-sharing bioctahedral [N(n-Bu)4]3[Re2(mnt)5] is reported here. Despite the short intermetal bond length of 2.6654(2) Å with computed bond order of 1.2, the unpaired electron is localised by the asymmetric ligand distribution, as demonstrated by its remarkable EPR spectrum

Monoclinic form of 1,2,4,5-tetra­cyclo­hexyl­benzene

The mol­ecule of the title compound, C30H46, has a crystallographically imposed inversion center and the cyclo­hexyl groups are oriented with their methine H atoms pointing towards one another (H⋯H = 1.99 Å). The cyclohexyl groups adopt chair conformations. A significant C—H⋯π inter­action assembles mol­ecules into layers parallel to (100)

Functional Characterization of the OPRM1 A118G Single Nucleotide Polymorphism in Mice

Endogenous opioids acting at μ-opioid receptors (MOPR) mediate many biological functions. Pharmacological intervention at these receptors has greatly aided in the treatment of acute and chronic pain, in addition to other uses. However, the development of tolerance and dependence has made it difficult to adequately prescribe these therapeutics. A common single nucleotide polymorphism (SNP), A118G, in the MOPR gene can affect opioid function and, consequently, has been suggested to contribute to individual variability in pain management and drug addiction. Investigation into the role of A118G in human disease and treatment response has generated a large number of association studies across various disease states as well as physiological responses. However, characterizing the functional consequences of this SNP and establishing if it causes or contributes to disease phenotypes have been significant challenges. To clarify the functional mechanisms linking the OPRM1 A118G SNP to addiction and analgesia phenotypes, we derived a mouse model possessing the equivalent nucleotide/amino acid substitution in the mouse Oprm1 gene. I first evaluated MOPR expression and function using molecular and pharmacological techniques and, subsequently, investigated how these alterations affected basal and morphine-evoked responses using a variety of behavioral tasks. In order to better understand the synaptic and circuit-level alterations conferred by this SNP, we employed voltage-sensitive dye imaging in hippocampal slice preparations to evaluate basal and opioid-stimulated neuronal responses. Mice harboring this SNP (A112G) demonstrated several phenotypic similarities to humans carrying the A118G SNP, including reduced mRNA expression and morphine-mediated antinociception. We found additional phenotypes associated with this SNP including significant reductions of receptor protein levels, morphine-mediated hyperactivity, and locomotor sensitization, as well as sex-specific reductions in the rewarding properties of morphine and the aversive components of naloxone-precipitated morphine withdrawal. Functionally, this SNP reduced opioid-stimulated excitatory responses in the hippocampus. Together, these findings extend our understanding of the functional consequences of this SNP and support evidence suggesting that this SNP results in a loss of receptor function. Further cross-species analysis will allow us to investigate mechanisms and adaptations present in humans carrying this SNP

Airborne Dispersal of San Jose Scale, Quadraspidiotus perniciosus (Comstock) (Homoptera: Diaspididae), Crawlers Infesting Apple

The aerial dispersal of San Jose scale, Quadraspidiotus perniciosus (Comstock), crawlers within the apple tree canopy and between trees was positively correlated with the seasonal abundance of crawlers on the bark. Airborne crawlers were significantly more abundant within the upper portions of the canopy and in the northeast and southeast quadrants. These data supported observations on variations in crawler density by location on the host and suggested that wind direction may have affected the distribution of crawlers dispersing aerially within the trees. The magnitude of aerial dispersal between trees was related to the levels of airborne dispersal within the canopy and the distance to the infested sourc

PHENOLOGY OF THE SAN JOSE SCALE (HOMOPTERA: DIASPIDIDAE) IN NEW YORK STATE APPLE ORCHARDS

Pheromone trapping studies from 1979 to 1981 showed that there were two periods of San Jose scale, Quadraspidiotus perniciosus (Comstock), male flight activity annually in western New York apple orchards. Spring flight, which resulted from overwintering black caps, began at ca. 94-140 degree-days (base 10 °C from 1 March) and occurred during bloom in the apple varieties studied. First generation crawlers emerged at ca. 360 degree-days. Second generation crawlers emerged at ca. 890 degree-days and were active throughout September. Regression analyses showed a logistic relationship between crawler density and fruit infestation, and inverse linear relationships between pheromone trap catches and San Jose scale infestation levels within tree

Ring Opening of Epoxides by Pendant Silanols

This document is the Accepted Manuscript version of a Published Work that appeared in final form in Organic Letters, copyright © 2022 American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see doi.org/10.1021/acs.orglett.1c04310We present a new ring-opening reaction of epoxides by pendant silanols, catalyzed by either Ph3C+BF4– or BINOL-phosphoric acid. Silanol epoxides derived from trans-allylic alcohols, cis-allylic alcohols, trans-homoallylic alcohols, and cis-homoallylic alcohols were all compatible and gave products from either endo- or exo-ring opening. With silanol epoxides derived from 4-alkenyl silanols, an unusual rearrangement to tetrahydrofuran products was observed. The utility of this methodology was demonstrated in a short preparation of protected d-arabitol

Expanding the scope of ligand substitution from [M(S2C2Ph2] (M = Ni2+, Pd2+, Pt2+) to afford new heteroleptic dithiolene complexes

The scope of direct substitution of the dithiolene ligand from [M(S2C2Ph2)2] [M = Ni2+ (1), Pd2+ (2), Pt2+ (3)] to produce heteroleptic species [M(S2C2Ph2)2Ln] (n = 1, 2) has been broadened to include isonitriles and dithiooxamides in addition to phosphines and diimines. Collective observations regarding ligands that cleanly produce [M(S2C2Ph2)Ln], do not react at all, or lead to ill-defined decomposition identify soft σ donors as the ligand type capable of dithiolene substitution. Substitution of MeNC from [Ni(S2C2Ph2)(CNMe)2] by L provides access to a variety of heteroleptic dithiolene complexes not accessible from 1. Substitution of a dithiolene ligand from 1 involves net redox disproportionation of the ligands from radical monoanions, –S•SC2Ph2, to enedithiolate and dithione, the latter of which is an enhanced leaving group that is subject to further irreversible reactions