Four new β-lactones from the endophytic Streptomyces sp. T1B1

Four new β-lactones including 4α-(3,5-dihydroxy-hexyl)-3α-methyl-2-oxetanone (1), 4α-(3-methyl-4-formyloxy-hexyl)-3α-methyl-2-oxetanone (2), 4α-(3,5-dihydroxy-heptyl)-3α-methyl-2-oxetanone (3) and 4α-(3-methyl-4-formyloxy-heptyl)-3α-methyl-2-oxetanone (4) were isolated from strain Streptomyces sp. T1B1.