[Observation of the pollen mother cell meiosis of male sterile line in rice by using confocal microscopy].

In the present paper, meiosis of male sterile pollen mother cells and fertility of ripened pollen was observed in male sterile line (Xindao97200A) by using laser scanning confocal microscopy (LSCM), beside, the seed setting rate of selfing and artificial pollination was investigated. Abnormal chromosome behaviors during the meiosis of PMC were found with 15.8%, which included lagging chromosome, dragging chromosomes, three poles of spindles, chromosome bridge, micronuclei and asynchrony of the dyad. Typical, spherical and stained abortive rates were 6.15%, 10.26% and 80.77%, respectively. The pollen abortion might be attributed to abnormal pollen development, which resulted from chromosome pairing abnormally, abnormal division, chromosome breakage and unevenly distributed cytoplasm.

Synthesis and evaluation of antitumor activities of novel chiral 1,2,4-triazole Schiff bases bearing γ-butenolide moiety.

BACKGROUND: 1,2,4-Triazole derivatives have received much attention due to their versatile biological properties including antibacterial, antifungal, anticonvulsant, antiinflammatory, anticancer, and antiproliferative properties. 1,2,4-Triazole nucleus has been incorporated into a wide variety of therapeutically interesting molecules to transform them into better drugs. Schiff bases of 1,2,4-triazoles have also been found to possess extensive biological activities. On the other hand, γ-substituted butenolide moiety represents a biological important entity that is present in numerous biologically active natural products. RESULTS: We have described herein the synthesis of 12 hybrid 1,2,4-triazole Schiff bases bearing γ-substituted butenolide moiety. These compounds were synthesized by utilizing the tandem asymmetric Michael addition/elimination reaction as the key step. All the new compounds were evaluated for their in vitro anticancer activity. CONCLUSIONS: Tandem asymmetric Michael addition/elimination approach has offered an easy access to new chiral 1,2,4-triazole compounds 7a-7l. All these chiral 1,2,4-triazole derivatives exhibited good anticancer activities towards Hela. Of all the tested compounds, the chiral compound 7l with an IC50 of 1.8 µM was found to be the most active.