Expanding the Boxmi Ligand Family: Synthesis and Application of NON and NSN Ligands.

Two synthetic strategies for a new family of neutral NON ligands featuring a "bis(oxazolinylmethylidene)isobenzofuran" framework (boxman) are reported. A Pd-mediated cyclization reaction forming the isobenzofuran core constitutes the key reaction in the eight-step synthetic route to the nonbackbone-methylated target compound H,Rboxman. In contrast, the introduction of two additional methyl groups provides stereochemical control during backbone construction and thereby access to the methylated derivative Me,Rboxman, which was synthesized in five steps and improved yields. In addition, the synthetic sequence was transferred to the thio analogue, providing access to the NSN ligand H,Rboxmene. Subsequent complexation experiments with iron and cobalt chloride precursors afforded the four-coordinated chlorido complexes Me,RboxmanMCl2 (R = Ph, iPr; M = Fe, Co) and established the boxman family as trans-chelating, bidentate bis(oxazoline) ligands. Application of the latter in the nickel(II)- and zinc(II)-catalyzed α-fluorination of ß-ketoesters and oxindoles (up to 98% yield and 94% ee) demonstrated their suitability for enantioselective catalysis.

Nucleophilic Substitution of gem-Difluoroalkenes with TMSNu Promoted by Catalytic Amounts of Cs2CO3.

The efficient and practical nucleophilic cyanation and trifluoromethylation with appropriate trimethylsilyl nucleophiles were developed. Catalytic amounts of cheap and nontoxic Cs2CO3 were used to maintain a sufficiently high concentration of nucleophilic anion (CN- or CF3-) which could begin the catalytic cycle. The present methodologies provide diverse functionalized monofluoroalkenes bearing a cyano and trifluoromethyl group with excellent to moderate stereoselectivities.

Jinfeng pills ameliorate premature ovarian insufficiency induced by cyclophosphamide in rats and correlate to modulating IL-17A/IL-6 axis and MEK/ERK signals.

ETHNOPHARMACOLOGICAL RELEVANCE: Jinfeng Pill (JFP) is a classical Chinese medicine formula and composed of 9 herbs, including Epimedium brevicornu Maxim (Yinyanghuo), Cervus elaphus Linnaeus (Lurong), Panax ginseng C.A.Mey. (Renshen), Equus asinus (EJiao), Ligustrum lucidum W.T.Aiton (Nvzhenzi), Reynoutria multiflora (Thunb.) Moldenke (Heshouwu), Curculigo orchioides Gaertn (Xianmao), Neolitsea cassia (L.) Kosterm. (Rougui) and Leonurus japonicus Houtt. (Yimucao). The formula is clinically used to regulate menstrual cycle and alleviate polycystic ovarian syndrome due to its capabilities of ovulation induction. It is therefore presumed that JFP could be used for the therapy of premature ovarian insufficiency (POI) but the assumed efficacy has not been fully substantiated in experiment. AIM OF STUDY: To evaluate the effectiveness of JFP on cyclophosphamide (CTX)-induced POI and preliminarily explore its potential mechanisms of action. MATERIAL AND METHODS: An experimental rat model of POI was established by using CTX induction to assess the efficacy of JFP. The potential targets of action for JFP alleviating POI were predicted by the combination of network pharmacology and transcriptomics and finally validating by RT-qPCR and Western blot. RESULTS: JFP alleviated the damages of ovarian tissue induced by CTX in the rat model of POI via significantly decreasing serum levels of FSH and LH and the ratio of FSH/LH and increasing the levels of E2 and AMH, accompanied with promoting ovarian folliculogenesis and follicle maturity and reversing the depletion of follicle pool. With the analysis of network pharmacology, pathways in cancer, proteoglycans in cancer, PI3K-AKT, TNF and FoxO signaling pathways were predicted to be influenced by JFP. The results of RNA-seq further revealed that IL-17 signaling pathway was the most important pathway regulated by both CTX and JFP, following by transcriptional misregulation in cancer and proteoglycans in cancer. Combining the two analytical methods, JFP likely targeted genes associated with immune regulation, including COX-2, HSP90AA1, FOS, MMP3 and MAPK11 and pathways, including IL-17,Th17 cell differentiation and TNF signaling pathway. Finally, JFP was validated to regulate the mRNA expression of FOS, FOSB, FOSL1, MMP3, MMP13 and COX-2 and decrease the release of IL-17A and the protein expression of IL-6 and suppress the phosphorylation of MEK1/2 and ERK1/2 in CTX induced POI rats. CONCLUSION: Jinfeng Pill is effective to ameliorate the symptoms of POI induced by CTX in the model of rats and its action is likely associated with suppressing IL-17A/IL-6 axis and the activity of MEK1/2-ERK1/2 signaling.

Enantioselective construction of cis-hydroindole scaffolds via an asymmetric inverse-electron-demand Diels-Alder reaction: application to the formal total synthesis of (+)-minovincine.

cis-Hydroindole scaffolds widely exist in a large number of natural products, pharmaceuticals, and organocatalysts. Therefore, the development of efficient and enantioselective methods for the construction of cis-hydroindoles is of great interest and importance. Herein, a novel approach for the enantioselective synthesis of cis-hydroindole scaffolds has been realized through a chiral N,N'-dioxide/Mg(OTf)2 complex catalyzed asymmetric inverse-electron-demand Diels-Alder (IEDDA) reaction of 2-pyrones and cyclic enamines. A series of substituted cis-hydroindole derivatives bearing multiple contiguous stereocenters and functional groups were obtained in good to excellent yields and enantioselectivities (up to 99% yield, and 95% ee) under mild reaction conditions. Moreover, the enantioselective formal total synthesis of (+)-minovincine was concisely furnished with high efficiency and stereoselectivity to demonstrate the synthetic potential of this method.

Rhodium-Catalyzed Successive C-H Bond Functionalizations To Synthesize Complex Indenols Bearing a Benzofuran Unit.

An efficient rhodium-catalyzed redox-neutral annulations of N-phenoxyacetamides and ynones via successive double C-H bond activations has been developed. A series of novel and complex indenols bearing a benzofuran unit were generated with moderate to excellent regioselecetivities under mild conditions. Adding N-ethylcyclohexanamine (CyNHEt) could restrict the formation of the mono C-H bond activation byproduct, which is not the intermediate of the reaction demonstrated via the mechanistic investigations.

Enantioselective Copper-Catalyzed Electrophilic Dearomative Azidation of ß-Naphthols.

The first example of copper-catalyzed enantioselective dearomative azidation of ß-naphthols using a readily available N3-transfer reagent is reported. A series of 2-hydroxy-1-naphthamides bearing a complex N-substituent were converted to the corresponding products in high yields with up to 96% ee, and chiral 1-azido-2-hydroxy-1-naphthoates were obtained with up to 90% ee under mild reaction conditions. The azides could be further transformed into the corresponding 1,2,3-triazoles smoothly via "click" reaction.