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This article discusses the synthesis and evaluation of saponins with all-nitrogenated sugars (ANS). Aminosugars, a class of modified carbohydrates, have been found in aminoglycosides but have limitations. The creation of artificial aminosugars, such as ANS, offers new possibilities for drug development. Saponins, derived from steroids and triterpenoids, have various biological activities and their sugar moiety plays a critical role. The article describes the synthesis of various ANS-saponin derivatives and their cytotoxicity, showing that ANS-saponins induce apoptosis. [Extracted from the article]

Totally substituted butenolide including two tetrasubstituted olefins is a distinct structural motif seen in Stemona alkaloids, but efficient methods for its synthesis are not well developed. As an ongoing program aimed at the collective total synthesis of the stemoamide group, we report a stereodivergent method to give either (E)- or (Z)-totally substituted butenolide from the same intermediate. While AgOTf--mediated elimination via an E1-type mechanism results in the formation of the kinetic (Z)-tetrasubstituted olefin, subsequent TfOH-mediated isomerization gives the thermodynamic (E)-tetrasubstituted olefin. The pyrrole ring is another important structure found in Stemona alkaloids. The direct oxidation of pyrrolidine rings with MnO2 and careful purification gives the pyrrole groups without isomerization of the stereocenter in the lactone group. These two methods enabled us to synthesize a series of stemoamide-type alkaloids including tricyclic, tetracyclic, and pentacyclic frameworks. The anti-inflammatory activities by inhibition of iNOS expression in macrophage cell line RAW264.7 indicate that the most potent anti-inflammatory compounds without cytotoxicity are protostemonines, which consist of pentacyclic frameworks including the totally substituted butenolide. [ABSTRACT FROM AUTHOR]

[Display omitted] Basidalin, isolated from the basidiomycete Leucoagaricus naucina , has previously demonstrated antibacterial and antitumor properties against murine cancer cells in vivo , but its effects on human cancer cells remain unknown. In this study, we found that basidalin possesses antiproliferative activity against human cancer cell lines. To elucidate the antiproliferative mechanism of basidalin, we focused on autophagy. Treatment with basidalin led to an increase in LC3-II expression level, and accelerated autophagic flux through an mTOR-independent pathway. Moreover, according to the structure–activity relationship analysis—including newly synthesized basidalin analogs—the formyl group, not the amino group, contributes to the antiproliferative activities of basidalin against human cancer cells. Additionally, the antiproliferative activity of basidalin analogs was strongly correlated with autophagy-inducing activity, indicating that basidalin exhibits antiproliferative activity through autophagy induction. These data suggest that basidalin, characterized by its ability to upregulate autophagic flux, emerges as a novel anticancer drug. [ABSTRACT FROM AUTHOR]