Recent advances in the synthesis of ferrocene derivatives via 3d transition metal-catalyzed C-H functionalization.

In recent years, transition-metal-catalyzed C-H functionalization has gradually developed into a powerful tool for the synthesis of ferrocenes in an atom- and step-economic fashion. However, despite significant achievements, the vast majority of these C-H functionalizations required precious 4d or 5d transition metal catalysts. The use of inexpensive and sustainable 3d metals in the C-H functionalization of ferrocenes remains challenging, especially the development of asymmetric versions. Herein, we summarize the remarkable recent progress in the synthesis of ferrocenes by 3d transition metal-catalyzed C-H activation until December 2021.

In vitro studies of deferasirox derivatives as potential organelle-targeting traceable anti-cancer therapeutics.

We report here strategic functionalization of the FDA approved chelator deferasirox (1) in an effort to produce organelle-targeting iron chelators with enhanced activity against A549 lung cancer cells. Derivative 8 was found to have improved antiproliferative activity relative to 1. Fluorescent cell imaging revealed that compound 8 preferentially localises within the lysosome.

Cp*Co(III)/MPAA-Catalyzed Enantioselective Amidation of Ferrocenes Directed by Thioamides under Mild Conditions.

Cp*Cobalt(III)-catalyzed enantioselective C-H amidation of ferrocenes using monoprotected amino acids (MPAAs) as chiral ligands was developed. The reaction was performed under mild conditions in high yields (up to 97%) with moderate enantioselectivity (up to 77.5:22.5 er), providing a promising strategy to create planar chirality via base-metal-catalyzed enantioselective C-H activation.

Amide-Directed Cobalt(III)-Catalyzed C-H Amidation of Ferrocenes.

The amide-directed cobalt(III)-catalyzed C-H amidation of ferrocene carboxamides using 1,4,2-dioxazol-5-ones as robust and efficient amidating reagents has been developed. This reaction proceeds efficiently under mild reaction conditions with good functional group tolerance, providing expedient access to a broad range of ferrocenes containing a nitrogen group on the Cp ring.

Scalable, Stereocontrolled Formal Syntheses of (+)-Isoschizandrin and (+)-Steganone: Development and Applications of Palladium(II)-Catalyzed Atroposelective C-H Alkynylation.

Dibenzocyclooctadiene lignans are an interesting class of molecules because of their unique structure based on an axially chiral biaryl moiety as well as their significant biological activity. Herein, we describe the development of a palladium-catalyzed atroposelective C-H alkynylation and its application in gram-scale, stereocontrolled formal syntheses of (+)-isoschizandrin and (+)-steganone. tert-Leucine was identified as an efficient, catalytic transient chiral auxiliary. A wide range of enantiomerically enriched biaryl compounds were prepared by this approach in good yields (up to 99 %) with excellent enantioselectivity (up to >99 % ee).

Ru-Catalyzed Meta-C-H Benzylation of Arenes with Toluene Derivatives.

The Ru-catalyzed meta-C-H benzylation of arenes bearing pyridyl, pyrimidyl, and pyrazolyl directing groups with toluene derivatives has been reported. Heptafluoroisopropyl iodide (iC3F7I) was employed as both a mild oxidant and radical initiator. This reaction showed excellent site-selectivity and tolerated a wide range of functional groups, providing a new strategy for the synthesis of various diarylmethane moieties.

Expression and functional role of Cdx2 in intestinal metaplasia of cystitis glandularis.

PURPOSE: Cdx2 is an essential transcription factor in intestinal epithelial cell differentiation and proliferation. However, to our knowledge the expression and role of Cdx2 in the development of intestinal cystitis glandularis, a metaplastic lesion induced by chronic inflammation, remained to be explored. MATERIALS AND METHODS: Real-time polymerase chain reaction was used to examine Cdx2, LI-cadherin and villin expression in typical and intestinal cystitis glandularis, and normal bladder tissue. Cdx2 cDNA was subcloned to the retroviral vector pLNCX2 for subsequent transfection into human bladder urothelium cells and rat bladder urothelium. Cdx2 mRNA and protein levels, and cell morphology and proliferation were assessed after transfection using real-time polymerase chain reaction, phase contrast microscopy, transmission electron microscopy and MTT assay, respectively. RESULTS: Higher mRNA levels of Cdx2, villin and LI-cadherin were detected in intestinal cystitis glandularis compared to normal bladder and typical cystitis glandularis. Only Cdx2 groups attained statistical significance (p <0.001). Retroviral over expression of Cdx2 resulted in increased mRNA and protein expression of Cdx2 as well as villin and LI-cadherin levels, and increased cell proliferation. A distinct change in cellular morphology, in which cells resembled intestinal-like cells, was also observed in vitro and in vivo. CONCLUSIONS: Cdx2 may have a critical role in regulating intestinal metaplasia in cystitis glandularis. Further studies are planned to assess the potential of using Cdx2 as a marker and therapeutic target for cystitis glandularis.