Abstract Three hydrazone ligands, H 2 L1 – H 2 L3 , made from salicylaldehyde and ibuprofen‐ or naproxen‐derived hydrazides, were prepared and transformed into the corresponding copper(II) complexes [Cu II L1 ]⋅H 2 O, [Cu II L2 ], and [(Cu II ) 2 ( L3 ) 2 ]⋅H 2 O⋅DMF ( Scheme ). The X‐ray crystal structure of the last‐mentioned complex was solved ( Fig. 1 ), showing a square‐planar complexation geometry, and the single units were found to form a one‐dimensional chain structure ( Fig. 2 ). The interactions of these complexes with CT‐DNA were studied by different techniques, indicating that they all bind to DNA by classical and/or non‐classical intercalation modes.
Abstract In THF solution, NaBH 4 in the presence of ( S )‐(‐)‐1‐(2‐chlorophenyl)‐2,2‐dimethylpropane‐1,3‐diol together with 2‐chlorobenzoic acid reduced propiophenone to 1‐ phenylpropan‐1‐ol in up to 40% enantiomeric excess ( ee ). Only 21% ee was obtained without an added acid. ( R )‐(‐)‐butane‐1,3‐diol and (R)‐( + )‐1,1′‐binaphthalene‐2,2′‐diol did not form clear solutions with NaBH 4 in THF and only gave a low ee. Of the organic acid additives investigated, ( S )‐(–)‐4‐(2‐chlorophenyl)‐5,5‐dimethyl‐2‐hydroxy‐1,3,2‐dioxaphosphorinane 2‐oxide gave the highest ee (46%). However, with AlCl 3 /NaBH 4 /( S )‐(–)‐1‐(2‐chlorophenyl)‐2,2‐dimethylpropane‐1,3‐diol in THF the best result was obtained ( ee 55%). Asymmetric Meerwein‐Ponndorf‐Verley (MPV) reductions of acetophenone by isopropanol in the presence of these chiral diols as auxiliary have also been carried out. For the case of aluminium triisopropoxide, ( R )‐(–)‐1‐phenyl‐2,2‐dimethylpropane‐1,3‐diol and acetophenone(1/1/1), an ee of up to 20% for 1‐phenylethanol was obtained whereas with ( R )‐(+)‐1,1′‐binaphthalene‐2,2′‐diol an ee of 32% was obtained. Lanthanide triisopropoxides, Ln(O i Pr) 3 , have also been used. Of the various lanthanides (Ln = La, Y, Er, Tb, and Eu) the Er triisopropoxide with chiral ( R )‐(–)‐1‐phenyl‐2,2‐dimethyl‐propane‐1,3‐diol gave the best result; 46% ee for 1‐phenylethanol. Lanthanide chloride diisopropoxides, LnCl(O i Pr) 2 , were also used as catalysts; although these have high catalytic activities they unfortunately give little chiral recognition.
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Few studies on cluster-based synthetic effects of multiple risk factors for birth defects have been reported. The present study aimed to identify maternal exposure clusters, explore the association between clusters of risk factors and birth defects, and further screen women with high risk for birth defects among expectant mothers.Data were drawn from a large-scale, retrospective epidemiological survey of birth defects from 2006 to 2008 in six counties of Shanxi Province, China, using a three-level stratified random cluster sampling technique. Overall risk factors were extracted using eight synthetic variables summed and examined as a total risk factor score: maternal delivery age, genetic factors, medical history, nutrition and folic acid deficiency, maternal illness in pregnancy, drug use in pregnancy, environmental risk factors in pregnancy, and unhealthy maternal lifestyle in pregnancy. Latent class cluster analysis was used to identify maternal exposure clusters based on these synthetic variables. Adjusted odds ratios (AOR) were used to explore associations between clusters and birth defects, after adjusting for confounding variables using logistic regression.Three latent maternal exposure clusters were identified: a high-risk (6.15%), a moderate-risk (22.39%), and a low-risk (71.46%) cluster. The prevalence of birth defects was 14.08%, 0.85%, and 0.52% for the high-, middle- and low-risk clusters respectively. After adjusting for maternal demographic variables, women in the high-risk cluster were nearly 31 times (AOR: 30.61, 95% CI: [24.87, 37.67]) more likely to have an infant with birth defects than low-risk women.A high-risk group of mothers in an area with a high risk for birth defects were screened in our study. Targeted interventions should be conducted with women of reproductive age to improve neonatal birth outcomes in areas with a high risk of birth defects.
Abstract (2 R ,4 S ,5 S )‐(+)‐5‐(2,2‐Dichloroacetamido)‐4‐(4‐nitrophenyl)‐2‐aryl‐1,3‐dioxanes 3–8 were synthesized with high diastereoselectivity and good yields. The structures of acetals were determined and the configurations were confirmed by 2D‐NMR (NOESY) and X‐ray crystallographic analysis.
OBJECTIVE To provide a new process for preparing CA-4 used as an agnet for anti-tumour. METHOD The product was synthesized from inexpensive isovanillin by six-step reactions. RESULT The chemical structure of the product was determined by IR and 1 HNMR. CONCLUSION The method is suitable for industry.
An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
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