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NIMA-related protein kinase Nek1 is crucially involved in cell cycle regulation, DNA repair and microtubule regulation and dysfunctions of Nek1 play key roles in amyotrophic lateral sclerosis (ALS), polycystic kidney disease (PKD) and several types of radiotherapy resistant cancer. Targeting of Nek1 could reveal a new class of radiosensitizing substances and provide useful tools to better understand the aforementioned diseases. In this report we explore substituted aminopyrazoles and 7-azaindoles as potent inhibitors for the Nek1 kinase domain and examine their effect on kidney organogenesis in Danio rerio., (Copyright © 2021 Elsevier Ltd. All rights reserved.)

The utilization of a dehydrated fungal biocatalyst of Aspergillus oryzae cells was successfully performed to achieve efficient acylation modification of a polar nucleoside cytarabine (ara-C). Organic solvents showed evident influence on the reaction catalyzed by the A. oryzae whole-cells. Except for hexane-pyridine, the catalytic activity and regioselectivity of the whole-cells clearly increased with increasing the polarity of the hydrophobic organic solvents used. The effects of some crucial factors on the reaction were further examined. The best reaction medium, hydrophobic solvent concentration, vinyl propionate/ara-C ratio, reaction temperature and shaking speed were confirmed as isopropyl ether (IPE)-pyridine, 30% (v/v), 90, 30 °C and 140-180 rpm, respectively. The cell biocatalyst also showed good thermal stabilities in both IPE-pyridine and hexane-pyridine systems. In addition, the desired 3'-O-propional derivative of ara-C was synthesized with the yields of 88.3% and regioselectivity (>70%). The resulting biocatalytic system appears to be an effective alternative, and can thus be employed for application in highly regioselective modification of nucleoside analogues., (Copyright © 2014. Published by Elsevier Ltd.)

Regioselective enzymatic acylations of 1-beta-D-arabinofuranosylcytosine (ara-C) with vinyl laurate (VL) in binary organic solvents were explored for the preparation of 5'-O-laurate of ara-C. Among the nine kinds of enzymes, Novozym 435 showed the highest regioselectivity (>99.9%) towards the 5'-OH of ara-C. This lipase showed higher catalytic activity in hexane-pyridine than in other tested solvent mixtures. The most suitable VL to ara-C molar ratio, initial water activity, and reaction temperature were shown to be 15:1, 0.07, and 50 degrees C, respectively, under which the initial reaction rate and the maximum substrate conversion were as high as 84.0 mmol L(-1) h(-1) and 98.1%, respectively. The product of Novozym 435-catalyzed acylation was characterized by (13)C NMR and confirmed to be 5'-O-laurate of ara-C., (2010 Elsevier Ltd. All rights reserved.)