Synthesis and Insecticidal Activity of 1- and 2-Indanyl Chrysanthemates

Indanyl 1- and 2-alcohols have been found to be a new entry in the list of “active alcohols” as the alcohol part of pyrethroids. Various substituted indanyl chrysanthemates were prepared and their insecticidal activity was tested on American cockroachs. These esters generally showed the substantial insecticidal activity, in which 4-alIyl-1-indanyl ester 20c was more potent than allethrin. Examination of substituents on 1-indanyl esters afforded some interesting results that methyl and allyl groups on the 4-position of the indanol nucleus were excellent and that no obvious electronic effects were observed.     

Bacteria-induced static batch fungal fermentation of the diterpenoid cyathin A<Subscript>3</Subscript>, a small-molecule inducer of nerve growth factor

Cyathin A₃, produced by the fungus Cyathus helenae, is a member of the cyathane family of diterpene natural products. While many of the cyathanes display antibacterial/antimicrobial activity or have cytotoxic activity against human cancer cell lines, their most exciting therapeutic potential is derived from their ability to induce nerve growth factor (NGF) release from glial cells, making the cyathanes attractive lead molecules for the development of neuroprotective therapeutics to prevent/treat Alzheimer’s disease. To investigate if cyathin A₃ has NGF-inducing activity, we set out to obtain it using published C. helenae bench-scale fungal fermentations. However, to overcome nonproducing fermentations, we developed an alternative, bacteria-induced static batch fermentation approach to the production of cyathin A₃, as described in this report. HPLC, UV absorption spectra, and mass spectrometry identify cyathin A₃ in fungal fermentations induced by the timely addition of Escherichia coli K12 or Bacillus megabacterium. Pre-filtration of the bacterial culture abolishes cyathin A₃ induction, suggesting that bacteria-associated media changes or physical interaction between the fungus and bacteria underlie the induction mechanism. Through alteration of incubation conditions, including agitation, the timing of induction, and media composition, we optimized the fermentation to yield nearly 1 mg cyathin A₃/ml media, a sixfold increase over previously described yields. Additionally, by comparison of fermentation profiles, we reveal that cyathin A₃ biosynthesis is regulated by carbon catabolite repression. We have used an enzyme-linked immunosorbent assay to illustrate that cyathin A₃ induces NGF release from cultured glial cells, and therefore cyathin A₃ warrants further examination in the development of neuroprotective therapeutics.     

Evaluation of a soybean lectin-based method for the enrichment of erythroblasts.

We performed a comparative study of the enrichment of erythroblasts by a soybean agglutinin galactose-specific lectin method and a standardized magnetic cell-sorting (MACS) protocol. Blood samples, obtained from 11 pregnant women at between 11 and 40 weeks of gestation, were split and examined by each method in parallel. The number of erythroblasts recovered by the lectin method was approximately eightfold higher than the number obtained by MACS. Our data suggest that the lectin-based method may provide a better approach for the enrichment of rare fetal erythroblasts from maternal blood.