The Structure Of 2',3'-O-Isopropylideneuridine

C12HI6N206 is orthorhombic, P2x2121, with a = 19.890 (5), b = 12.789 (2), c = 5.236 (1) A, Z = 4, U = 1331.9/~ 3, F(000) = 600. Mo Ka (/~ = 0.123 mm -1) intensities for 940 unique reflections up to sin 0/2 = 0.538/k -1 were collected on a CAD-4 diffractometer. Final R = 0.034. The glycosidic torsion angle 2~CN is 3"4 °, significantly smaller than that (56.5 °) in 2',3'- -methoxymethyleneuridine (MMU). The ribose moiety has a C(3')-exo-C(4')-endo twist conformation, in contrast to the C(2')-endo conformation in MMU. However, the maximum amplitudes of pucker for the ribose and dioxolane rings are very nearly the same for the two structures. The conformation about C(4')-C(5') is gauche-gauche (~0oo = -68-4, Ooc = 51.3°).

Molecular-complexes of metallo tetraphenyl porphyrins with 2,4,5,7-tetranitro fluorenone

The interactions of mesotetraphenyl porphyrin and its metallo derivatives with 2,4,5,7-tetra nitrofluorenone have been studied using spectroscopic methods. The association constants (K) for 1:1 complexes in Ch2Cl2Cl2 follow the order Pd+2>Co+2> Cu+2>VO+2>Ni+2>Zn+2. The values of K are accounted in terms of stereochemistry of MTPPs and the electronic configuration of the metal ions. The magnitude and direction of the proton NMR shifts of the acceptor and donor in the complexes and their ESR parameter furnish information as to the possible structures of these complexes in solution.

2 Algorithms For 3-Layer Channel Routing

A channel router is an important design aid in the design automation of VLSI circuit layout. Many algorithms have been developed based on various wiring models with routing done on two layers. With the recent advances in VLSI process technology, it is possible to have three independent layers for interconnection. In this paper two algorithms are presented for three-layer channel routing. The first assumes a very simple wiring model. This enables the routing problem to be solved optimally in a time of O(n log n). The second algorithm is for a different wiring model and has an upper bound of O(n2) for its execution time. It uses fewer horizontal tracks than the first algorithm. For the second model the channel width is not bounded by the channel density.

Genome-wide association and genetic functional studies identify autism susceptibility candidate 2 gene (AUTS2) in the regulation of alcohol consumption

Alcohol consumption is a moderately heritable trait, but the genetic basis in humans is largely unknown, despite its clinical and societal importance. We report a genome-wide association study meta-analysis of approximately 2.5 million directly genotyped or imputed SNPs with alcohol consumption (gram per day per kilogram body weight) among 12 population-based samples of European ancestry, comprising 26,316 individuals, with replication genotyping in an additional 21,185 individuals. SNP rs6943555 in autism susceptibility candidate 2 gene (AUTS2) was associated with alcohol consumption at genome-wide significance (P = 4 x 10(-8) to P = 4 x 10(-9)). We found a genotype-specific expression of AUTS2 in 96 human prefrontal cortex samples (P = 0.026) and significant (P < 0.017) differences in expression of AUTS2 in whole-brain extracts of mice selected for differences in voluntary alcohol consumption. Down-regulation of an AUTS2 homolog caused reduced alcohol sensitivity in Drosophila (P < 0.001). Our finding of a regulator of alcohol consumption adds knowledge to our understanding of genetic mechanisms influencing alcohol drinking behavior.

Genome-wide association study identifies a locus at 7p15.2 associated with endometriosis

Endometriosis is a common gynecological disease associated with pelvic pain and subfertility. We conducted a genome-wide association study (GWAS) in 3,194 individuals with surgically confirmed endometriosis (cases) and 7,060 controls from Australia and the UK. Polygenic predictive modeling showed significantly increased genetic loading among 1,364 cases with moderate to severe endometriosis. The strongest association signal was on 7p15.2 (rs12700667) for 'all' endometriosis (P = 2.6 x 10(-)(7), odds ratio (OR) = 1.22, 95% CI 1.13-1.32) and for moderate to severe disease (P = 1.5 x 10(-)(9), OR = 1.38, 95% CI 1.24-1.53). We replicated rs12700667 in an independent cohort from the United States of 2,392 self-reported, surgically confirmed endometriosis cases and 2,271 controls (P = 1.2 x 10(-)(3), OR = 1.17, 95% CI 1.06-1.28), resulting in a genome-wide significant P value of 1.4 x 10(-)(9) (OR = 1.20, 95% CI 1.13-1.27) for 'all' endometriosis in our combined datasets of 5,586 cases and 9,331 controls. rs12700667 is located in an intergenic region upstream of the plausible candidate genes NFE2L3 and HOXA10.

2.2.2.2 Improved Management Summer Weeds: Best weed management strategies dryland cropping systems

To undertake a scoping study to identify the major issues in weed management in dryland cropping systems with cotton.

Inhibition of mitochondrial oxidative phosphorylation by 2-methyl-4-dimethylaminoazobenzene

The azodye 2-methyl-4-dimethylaminoazobenzene inhibited oxidation and phosphorylation in tightly coupled rat liver mitochondria. Phosphorylation was more sensitive to the inhibitory action of the azodye than was the oxidation of succinate or ascorbate. The oxidation of NAD+-linked substrate was severely inhibited by the compound. In submitochondrial particles, only NADH oxidation was sensitive. The site of inhibition has been identified to lie between the dehydrogenase flavoprotein and ubiquinone.

Some metal complexes with n-(2-pyridyl)thioacetamide and n-(2-pyridyl)thiobenzamide

The Cu(II). Zn(II) and Cd(II) chloride and bromide complexes of N-2(2-pyridyl)thioacetamide and N-(2-pyridyl)thiobenzamide have been prepared. The infrared and 1H and 13C NMR spectra of the complexes and the free ligands have been analysed to determine the coordination sites. It was concluded that N-(2-pyridyl)thioacetamide behaves as a bidentate ligand, chelating to the metal via pyridine nitrogen and thionamide sulfur atoms while the other ligand, N-(2-pyridyl)thiobenzamide coordinates to the metal atom as a unidentate through the pyridine nitrogen atom. Conformations of the free ligands are discussed.

Ternary metal complexes of anionic and neutral pyridoxine (vitamin B6) with 2,2'-bipyridine. Syntheses and x-ray structures of (pyridoxinato)bis(2,2'-bipyridyl)cobalt(III) perchlorate and chloro(2,2'-bipyridyl)(pyridoxine)copper(II) perchlorate hydrate

Ternary metal complexes involving vitamin B6 with formulas [CO",(PN-H)](anCdI [OC)'(bpy)(PN)Cl]C10(.bpHy 0 = 2,2'-bipyridine, PN = neutral pyridoxine, PN-H = anionic pyridoxine) have been prepared for the first time and characterized by means of magnetic and spectroscopic measurements. The crystal structures of the compounds have also been determined. [CO(PN-H)](CcryIsOta,l)lize s in the space group P2,/c with a = 18.900 (3) A, b = 8.764 (1) A, c = 20.041 (2) A,p = 116.05 (l)', and Z = 4 and [Cu(bpy)(PN)C1]C104-H20in the space group Pi with a = 12.136 (5) A, b = 13.283 (4) A,c = 7.195 (2) A, a = 96.91 (Z)', 0 = 91.25 (3)', y = 71.63 (3)', and Z = 2. The structures were solved by the heavy-atom method and refined by least-squares techniques to R values of 0.080 and 0.042 for 3401 and 2094 independent reflections, respectively. Both structures consist of monomeric units. The geometry around Co(II1) is octahedral and around Cu(I1) is distorted square pyramidal. In [CO(PN-H)]t(wCo IoxOy~ge)n~s ,fro m phenolic and 4-(hydroxymethyl) groups of PN-H and two nitrogens from each of two bpy's form the coordination sphere. In [Cu(bpy)(PN)C1]C104.H20o ne PN and one bpy, with the same donor sites, act as bidentate chelates in the basal plane, with a chloride ion occupying the apical position. In both structures PN and PN-H exist in the tautomeric form wherein pyridine N is protonated and phenolic 0 is deprotonated. However, a novel feature of the cobalt compound is that PN-H is anionic due to the deprotonation of the 4-(hydroxymethyl) group. The packing in both structures is governed by hydrogen bonds, and in the copper compound partial stacking of bpy's at a distance of -3.55 also adds to the stability of the system. Infrared, NMR, and ligand field spectroscopic results and magnetic measurements are interpreted in light of the structures.

1H and 13C NMR spectral studies of C-2 substituted isomeric exo- and endo-5-methyl-bicyclo[3.2.1]octane-6,8-diones

A detailed analysis of the 1H and 13C NMR spectra of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones is presented. The chemical shift of the C-5 angular methyl, the C-2 alkyl/olefinic (C-10)/C-2 methine protons, the aromatic proton shieldings and the characteristic AMX and ABX spectral pattern of the ketomethylene and bridgehead protons were found to be sensitive to the phenyl ring orientation (anisotropy). These distinctive features could be used for configurational distinction for this class of compounds. With increasing ortho-methoxy substitution on the phenyl ring, considerable deshilelding of the bridgehead proton was observed (ca. 0.6 ppm). Absence of the C-2 alkyl group in the desalkyl isomers resulted in substantial changes in the chemical shifts of different protons. A study of the NMR spectra of the corresponding bicyclic compounds with C-2 methoxy/hydroxy substitution instead of the aryl group revealed that the anisotropy of the phenyl ring and the electronegative oxygen substituents have opposite effects. The 13C NMR spectral assignment of each carbon resonance of C-2 aryl and alkyl/desalkyl substituted isomeric exo- and endo-5-methylbicyclo[3.2.1]octane-6,8-diones and the corresponding C-2 methoxy/hydroxy/chloro and methyl bicyclic compounds are reported. Additional ortho-methoxy substitution on the phenyl ring was found to produce considerable high field shifts of the C-10 and C-1 carbon resonances. A high-field shift was observed for the C-6 and C-8 carbonyl carbons, presumably due to 1,3-dicarbonyl interactions. The chemical shifts of C-1 aromatic, C-10 alkyl and C-2 carbons, which are sensitive to exo/endo isomerism, could be utilized in differentiating a pair of isomers.

3-Amino-1,2,4-triazole is an inhibitor of protein synthesis on mitoribosomes in Neurospora crassa

The effects of the herbicide, 3-amino-1,2,4-triazole, an inhibitor of heme synthesis in rat liver, have been examined in the mold Neurospora crassa. The drug is a potent inhibitor of the growth of the mold and produces biochemical changes identical to those produced by chloramphenicol. 3-Amino-1,2,4-triazole, like chloramphenicol, is a direct and specific inhibitor of protein synthesis on mitoribosomes. A decrease in the levels of mitochondrial proteins which are completely or partly made on mitoribosomes and an accumulation in the levels of mitochondrial proteins of cytosolic origin have been observed. Both drugs depress porphyrin and heme levels, but there is actually an elevation in the levels of δ-aminolevulinate dehydratase, the rate-limiting enzyme of the heme-biosynthetic pathway in Neurospora crassa. In liver the enzyme is present in non-limiting amounts and the levels are depressed under conditions of 3-amino-1,2,4-triazole treatment. In Neurospora crassa the ‘derepression’ of δ-aminolevulinate dehydratase under conditions of 3-amino-1,2,4-triazole or chloramphenicol treatment is only partial because the drugs inhibit protein synthesis on mitoribosomes. It is concluded that an optimal rate of protein synthesis on mitoribosomes is necessary to maintain an adequate rate of heme synthesis.