Electrochemically Driven Site-Selective N-Hydroxymethylation of Indoles and Derivatives.

Described herein is a facile electrochemical strategy for the generation of formaldehyde from N,N-dimethylacetamide (DMA) and water (HO) toward a direct and site-selective N-hydroxymethylation of indoles and derivatives. Mechanistic studies suggested that N-(hydroxymethyl)-N-methylacetamide generated in situ from DMA/HO under electrochemical conditions serves as a formaldehyde surrogate. The developed methodology features mild, base- and metal catalyst-free conditions.

Palladium-Catalyzed Double Decarboxylative [3 + 2] Annulation of Naphthalic Anhydrides with Internal Alkynes.

A palladium-catalyzed [3 + 2] annulation of naphthalic anhydrides with internal alkynes has been developed. The present protocol offers an efficient and convenient route to access a series of 1,2-disubstituted acenaphthylenes with excellent functional group compatibility. The reaction is proposed to proceed through a double decarboxylation sequence.

Electro-oxidative Methylation of 2-Isocyanobiaryls Using N,N-dimethylformamide (DMF) as Carbon Source: Synthesis of 6-Methylphenanthridines.

A benign electrochemical method to access 6-methylphenanthridines from 2-isocyanobiaryls using N,N-dimethylformamide (DMF) as a methyl source is reported. The protocol operates at ambient temperature without the need for harmful methylating reagents. Mechanistic studies suggested that DMF delivered a methylene synthon, followed by reduction at the cathode and tautomerization.

Mallotumides A-C: Potent Cytotoxic Cycloheptapeptides from the Roots of .

The structures of potent cytotoxic cycloheptapeptides, mallotumides A-C (-, respectively) isolated from the roots of Airy Shaw, were elucidated by extensive spectroscopic analysis. The absolute configuration of was determined by single-crystal X-ray crystallographic data. All three cycloheptapeptides exhibited potent cytotoxicity against various cancer cell lines with IC values ranging from 0.

Endoplasmic Reticulum Stress-Mediated Apoptosis Induced by VR12684 Isolated from Mallotus spodocarpus in Cholangiocarcinoma Cell Line.

Introduction: Cholangiocarcinoma (CCA) is a poor prognosis of a malignant tumor that has been unresponsive to conventional chemotherapeutic agents. Effective and novel therapeutic agents are urgently needed. VR12684 (isolated from Mallotus spodocarpus) has been reported to exhibit growth inhibitory activities in cancer cell lines.