文摘
Based on fungus–fungus pairing assays and HRMS-based dereplication strategy, six new cyclic tetrapeptides, pseudoxylallemycins A–F (1–6), were isolated from the termite-associated fungus Pseudoxylaria sp. X802. Structures were characterized using NMR spectroscopy, HRMS, and Marfey’s reaction. Pseudoxylallemycins B–D (2–4) possess a rare and chemically accessible allene moiety amenable for synthetic modifications, and derivatives A–D showed antimicrobial activity against Gram-negative human-pathogenic Pseudomonas aeruginosa and antiproliferative activity against human umbilical vein endothelial cells and K-562 cell lines.