One-pot oxidative hydrolysis-oxidative cleavage of 7-borylindoles enables access to o-amidophenols and 4-acylbenzoxazoles

Abstract

7-Borylindoles undergo a one-pot oxidative hydrolysis-oxidative cleavage process to give o-amidophenols, that in turn undergo facile cyclisation to give 4-acylbenzoxazoles.

Structurally Diverse Metabolites from the Marine‐Derived Streptomyces sp. DS‐27 Based on Two Different Culture Conditions

“…DS-27 was separately fermented on rice solid medium and Gause's liquid medium and extracted with AcOEt. The AcOEt extracts were subjected to silica gel and HPLC chromatography to afford nine new compounds (1-8 and 20), and sixteen known compounds including N-(1-amino-4-methyl-1-oxopentan-2-yl)-2-hydroxy-4-methylpentanamide (9), [5] 1,3-dihydroxy-5-isopropyl-2,4-dimethylbenzene (10), [6] S-methyl 2,4dihydroxy-6-isopropyl-3,5-dimethylbenzothioate (11), [6] 2hydroxy-5-isopropyl-2,4-dimethylfuran-3(2H)-one ( 12), [7] Nacetyl-D-tyrosine (13), [8] trans-p-coumaric acid ( 14), [9] N-acetyltryptophan (15), [10] (2E,6E)-2,6-dimethylocta-2,6-dienedioic acid ( 16), [11] 2-(acetylamino)-5-hydroxybenzoic acid (17), [12,13] 3-acetamido-3-(4-hydroxyphenyl)propanoic acid (18), [14] N-(2acetyl-6-hydroxyphenyl)acetamide ( 19), [15] phaeochromycins A (21), [16] phaeochromycins B (22), [16] phaeochromycins C (23), [16] 9-hydroxyphaeochromycins C (24), [17] and K 1115 A (25). [18] Among these, compounds 1-19 were isolated from solidfermented crude extracts, while compounds 20-24 were isolated from liquid fermentation extracts.…”