Selective methanolysis or dehydration followed by reduction of the 3-h
ydroxyglutamine residue of pneumocandin B-0 (1) or its dideoxy analog
5 (L-692,289) gave the methyl 3-hydroxyglutamate and 3-hydroxyornithin
e analogs 6 and 9, respectively. Further derivatization of these analo
gs allowed a study of the SAR at this position. In general, carboxylic
acid-containing derivatives were poorer antifungal agents than neutra
l derivatives while amine-bearing analogs displayed the greatest poten
cy.