Alstolarines A and B, two unusual monoterpenoid indole alkaloids with an acetal moiety from Alstonia scholaris

Abstract

Two novel monoterpenoid indole alkaloids, alstolarines A and B (1–2), were isolated from the leaves and twigs of Alstonia scholaris. Compound 1 is the first vobasinyl-type alkaloid with a 6/5/8/5/6/5...

Alscholarines A and B, two rearranged monoterpene indole alkaloids from Alstonia scholaris

“…8 To date, however, rare reports concern the isolation of MIAs from the branches of this plant. 7,21–23 In our previous chemical study on the branches of A. scholaris , structurally diverse and biologically active MIAs have been identified, encouraging us greatly. 24 As part of our effort to discover structurally unique and biogenetically interesting MIAs, we conducted in-depth research phytochemical investigations of the branches of A. scholaris , leading to the isolation of two novel complex MIAs (Fig.…”

Sharpless Asymmetric Dihydroxylation: An Impressive Gadget for the Synthesis of Natural Products: A Review

“…Depending upon the positioning of atoms, MIAs are divided into three categories, most of which are derived from different parts of Alstonia scholaris. Zhang et al in 2020 [ 35 ] proposed the total synthesis of two important MIAs, i.e., alstolarines A and B. They stated that the total synthesis could be initiated with the forerunner difforlemenine 20 , which could be subjected to reduction followed by ring opening reaction, leading to the generation of compound 21 .…”

Eco-friendly one-step synthesis of highly functionalized-spirooxindole-pyranopyrazoles and their in-vitro anticancer studies

“…Moreover, the core of isatin has been inspired due to the dioxindoles (DOXs) being transformed into various spirooxindoles using different chemical transformations. The conformational spirooxindoles (SOXs) have been isolated from a few fungi, plants, and animals, i.e., Aspergillus funmigetus, Mitragyna speciosa, Horsfieldia superb, Uncaria rhynchophylla, Alstonia muelleriana, and Penicillium roqueforti etc [11][12][13][14][15][16][17]. Screamingly, these naturally occurring SOXs, such as spirotryprostatine (A, B), are found in the fungus Aspergillus funmigetus and have anticancer properties.…”