Engineering an Epoxide Hydrolase for Chemoenzymatic Asymmetric Synthesis of Chiral Triazole Fungicide ()- and ()-Flutriafol.

Flutriafol, a globally utilized triazole fungicide in agriculture, is typically applied as a racemic mixture, but its enantiomers differ in bioactivity and environmental impact. The synthesis of flutriafol enantiomers is critically dependent on chiral precursors: 2,2-bisaryl-substituted oxirane [(2-fluorophenyl)-2-(4-fluorophenyl)oxirane, ] and 1,2-diol [1-(2-fluorophenyl)-1-(4-fluorophenyl)ethane-1,2-diol, ]. Here, we engineered a epoxide hydrolase (EH), obtaining mutant / with a 6.

Chemoenzymatic Asymmetric Synthesis of Chiral Triazole Fungicide ()-Tebuconazole in High Optical Purity Mediated by an Epoxide Hydrolase from .

Tebuconazole is a chiral triazole fungicide used globally in agriculture as a racemic mixture, but its enantiomers exhibit significant enantioselective dissimilarities in bioactivity and environmental behaviors. The steric hindrance caused by the -butyl group makes it a great challenge to synthesize tebuconazole enantiomers. Here, we designed a simple chemoenzymatic approach for the asymmetric synthesis of ()-tebuconazole, which includes the biocatalytic resolution of racemic epoxy-precursor (2--butyl-2-[2-(4-chlorophenyl)ethyl] oxirane, -) by / whole cells expressed epoxide hydrolase from (EH), followed by a one-step chemocatalytic synthesis of ()-tebuconazole.

Novel kojic acid derivatives with anti-inflammatory effects from Aspergillus versicolor.

Two novel kojic acid derivatives, kojicones A and B (1 and 2), along with the precursors kojic acid (3) and (2R,4R)-4-hydroxy-5-methoxy-2,4-dimethyl-2- [(2R)-2-methylbutyryloxy]-5-cyclohexen-1,3-dione (4), were isolated from a fungal strain Aspergillus versicolor. Their structures and absolute configurations were accurately confirmed by HRESIMS data, NMR analysis, and electronic circular dichroism (ECD) calculations. Kojicones A and B were the first examples of kojic acid adducts with cyclohexen-1,3-dione possessing unprecedented tricycle skeletons.

Antifungal Macrocyclic Trichothecenes from the Insect-Associated Fungus .

Three new macrocyclic trichothecenes possessing rare 6'-ketal moieties, roridoxins A-C (), and five known compounds () were isolated from the insect-associated fungus . Their structures were confirmed by a combination of NMR and HRESIMS data, while their absolute configurations were unambiguously determined by single-crystal X-ray analysis and electronic circular dichroism experiments. Trichothecenes and showed potent antifungal activities against four strains of phytopathogenic fungi.

Antioxidant coumarin and pyrone derivatives from the insect-associated fungus .

Two new compounds, versicolones A and B ( and ), and three known pyrone derivatives (-) were isolated from the insect-associated fungus . Their structures were elucidated through a combination of HRESIMS and NMR spectroscopic analysis. Versicolone A () was revealed as a coumarin derivative with the rare 5-alkyl side chain substitution.

Two cases of non-haematological cause of fetal hydrops in at-risk pregnancies for homozygous α0-thalassemia.

In recent years, sonography has been successfully used as an alternative method for prenatal detection of Hb Bart's disease in areas with high prevalence of α-thalassemia. We present two cases in which the fetuses demonstrated signs of Hb Bart's disease by sonography, however, invasive procedures could not confirm it. We recommend that, in prenatal diagnosis of Hb Bart's disease by sonography, the diagnosis should always be confirmed with definitive methods to exclude false-positive findings.

[Studies on safety of cordocentesis guided by transabdominal ultrasound for prenatal diagnosis].

Objective: To assess the safety and efficacy of diagnostic cordocentesis during pregnancy.

Methods: During March 1990 to June 2003, 2403 consecutive cordocenteses were performed under transabdominal ultrasound guidance at Guangzhou Women and Children's Hospital. The results of each procedure was prospectively collected and subsequently analysed in terms of operational complications and pregnancy outcomes.