We report the first secondary metabolite, 8,8′-bijuglone, obtained from pure cultures of the slow growing Douglas fir- (Pseudotsuga menziesii var. menziesii) foliage-associated fungus Zasmidium pseudotsugae. The quinone was characterized using extensive LC/MS and NMR-based spectroscopic methods. 8,8′-Bijuglone exhibited moderate antibiotic activity against Gram-positive pathogens and weak cytotoxic activity in the NCI-60 cell line panel and in our in-house human colon carcinoma (HCT-116) cell line. An analysis of the fungal genome sequence to assess its metabolic potential was implemented using the bioinformatic tool antiSMASH. In total, 36 putative biosynthetic gene clusters were found with a majority encoding for polyketides (17), followed by non-ribosomal peptides (14), terpenes (2), ribosomal peptides (1), and compounds with mixed biosynthetic origin (2). This study demonstrates that foliage associated fungi of conifers produce antimicrobial metabolites and suggests this guild of fungi may present a rich source of novel molecules. 
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                            Synthesis of Thiazole‐Fused Diosgenin Derivatives as Potential Therapeutic Agents
                        
                    
    
            Abstract Diosgenin, a hydrolyzed product of phytosteroid saponin, has widely been studied for its medicinal properties. In an effort to find bioactive molecules, 25 novel thiazole‐fused diosgenin molecules have been synthesized by an efficient reaction protocol. The chemistry involves the Oppenauer oxidation followed by double bond isomerization in a one‐pot reaction, epoxidation, and the reaction of urea derivatives with the epoxyketone to synthesize the target compounds. These novel chimeric compounds were tested for their potential antimicrobial and cytotoxic properties. Antimicrobial studies against a panel of Gram‐positive and Gram‐negative led to the discovery of some of these molecules as narrow‐spectrum antimicrobial agents againstBacillus subtilisbacteria. In preliminary cytotoxicity studies, 2‐fluorophenyl derivative (10) inhibited the growth of several cell lines of the NCI‐60 cell line panels including >93 % inhibition of UO‐31 cell line. Furthermore, the hit antibacterial compounds are non‐toxic to human cancer cell lines, and the cytotoxic compound is not active against the bacterial strains, showing the selective therapeutic potential of the chimeric compounds. 
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                            - Award ID(s):
- 2117138
- PAR ID:
- 10553027
- Publisher / Repository:
- Wiley
- Date Published:
- Journal Name:
- ChemistrySelect
- Volume:
- 9
- Issue:
- 40
- ISSN:
- 2365-6549
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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