Simple, inexpensive, highly active, recoverable and reusable proline-based organocatalysts have been developed to promote direct stoichiometric aldol reactions with excellent enantioselectivities. The proline-based organocatalyst 1c is highly efficient for the stoichiometric aldol reactions of a wide range of aromatic aldehydes with cyclic ketones, and the resulting aldol products could be obtained with up to 99 : 1 anti/syn ratio and 499% ee. The proline-based organocatalyst 1c can be easily recovered and reused, and only a slight decrease in enantioselectivities was observed after seven cycles. The prolinebased organocatalyst 1c can be efficiently applied to large-scale reactions with the enantioselectivities being maintained at the same level, which demonstrates potential application in industry.
This study is aimed to investigate the mechanisms of radiation-induced mouse models of premature ovarian insufficiency (POI). Wistar female rats were grouped into the control, 3.2 Gy, 4.0 Gy, and 4.8 Gy groups. Overall ovarian functions were assessed with the H&E staining and ELISA. Proinflammatory cytokine secretion was analyzed ELISA, and the reactive oxygen species (ROS) levels were analyzed with immunohistochemistry. Protein expressions were analyzed by Western blot analysis. The 4.0 Gy and 4.8 Gy groups had significantly lower ovarian weight coefficients than the control and 3.2 Gy groups (after only one irradiation therapy). The 3.2 Gy radiation group induced periodic disturbance and hormone change at 4 weeks after radiation. In the 4.0 Gy and 4.8 Gy groups, the preantral follicles and antral follicles were decreased, while Atresia follicles were increased. E2 was decreased, while FSH and LH secretions were increased. The ovaries in the 4.0 Gy group were not completely atrophied, and some preantral follicles remained. Ovarian atrophy and follicular Atresia were found in the 4.8 Gy group. Inflammatory and oxidative markers were upregulated. PI3K and AKT were downregulated in the 4.0 Gy and 4.8 Gy groups, while FOXO3a was upregulated. Ovarian injuries may lead to oxidative damages and inflammatory injuries, downregulate the expression of P13k and Akt, upregulate the expression of FOXO3a, and lead to follicular atresia in the ovary.
A completely non-chromatographic and highly large-scale adaptable synthesis of zirconium poly(styrene-phenylvinylphosphonate)phosphate-supported l-proline (ZrPS-PVPA-Pr) has been developed in only three steps overall.
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