Discovery of novel simplified isoxazole derivatives of sampangine as potent anti-cryptococcal agents.
Cryptococcus neoformans is the leading cause of cryptococcal meningitis, which is associated with high mortality due to lack of effective treatment. Herein a series of tricyclic isoxazole derivatives with excellent anti-cryptococcal activities were identified by structural simplification and scaffold hopping of antifungal natural product sampangine. Particularly, compound 8a showed promising features as an anti-cryptococcal lead compound. It was highly active against C. neoformans (MIC80 = 0.031 μg/mL), which was more potent than fluconazole and voriconazole. Moreover, compound 8a showed potent fungicidal activity and had potent inhibitory effects against important virulence factors (i.e. biofilm, melanin and urease) of C. neoformans. Preliminary antifungal mechanism investigation revealed that compound 8a induced apoptosis of C. neoformans cells and arrested the cell cycle at the G1/S phase.
['Li|Zhuang|Z|', 'Liu|Na|N|', 'Tu|Jie|J|', 'Ji|Changjin|C|', 'Han|Guiyan|G|', 'Wang|Yan|Y|', 'Sheng|Chunquan|C|']
D000470:Alkaloids D000935:Antifungal Agents D017209:Apoptosis D018441:Biofilms D003455:Cryptococcus neoformans D055808:Drug Discovery D059585:G1 Phase Cell Cycle Checkpoints D006576:Heterocyclic Compounds, 4 or More Rings D007555:Isoxazoles D008543:Melanins D008826:Microbial Sensitivity Tests D015394:Molecular Structure D009287:Naphthyridines D013329:Structure-Activity Relationship D014510:Urease
Anti-cryptococcal Structural simplification Fungicidal activity Virulence factors Antifungal mechanism