Figure 1
Structures of the tested furanones. Synthesis of furanones related to Streptomyces antibioticus metabolites and chemical structure of the compounds tested. A) general scheme for the synthesis of furanones related to Streptomyces antibioticus metabolites; reagents: a: Lithium diisopropylamide, b: BBr3, c: NaBH4 B) synthesized compounds (for details [29]).1.01: 5-hydroxy-4-methylfuran-2(5H)-one a), 3.01: 5-hydroxy-3-[(1R)-1-hydroxyethyl]-4-methylfuran-2(5H)-one b), 3.02: 5-hydroxy-3-[(1S)-1-hydroxyethyl]-4-methylfuran-2(5H)-one b), 3.11: 5-hydroxy-3-[(1R)-1-hydroxypropyl]-4-methylfuran-2(5H)-one b), 3.12: 5-hydroxy-3-[(1S)-1-hydroxypropyl]-4-methylfuran-2(5H)-one b), 3.21: 5-hydroxy-3-[(1R,2S)-1-hydroxy-2-methylbutyl]-4-methylfuran-2(5H)-one b), 3.22: 5-hydroxy-3-[(1S,2S)-1-hydroxy-2-methylbutyl]-4-methylfuran-2(5H)-one b), 3.31: 5-hydroxy-3-[(1R)-1-hydroxy-2,2-dimethylpropyl]-4-methylfuran-2(5H)-one b), 3.32: 5-hydroxy-3-[(1S)-1-hydroxy-2,2-dimethylpropyl]-4-methylfuran-2(5H)-one b), 3.41: 5-benzyloxy-3-bromo-4-methylfuran-2(5H)-one b), [63] 3.51: 5-hydroxy-3-(1-hydroxydecyl)-4-methylfuran-2(5H)-oned), 4.01: 3-[(1R)-1-hydroxyethyl]-4-methylfuran-2(5H)-one, 4.02: 3-[(1S)-1-hydroxyethyl]-4-methylfuran-2(5H)-one, 4.11: 3-[(1R)-1-hydroxypropyl]-4-methylfuran-2(5H)-one, 4.12: 3-[(1S)-1-hydroxypropyl]-4-methylfuran-2(5H)-one, 4.21: 5-hydroxy-3-[(1R,2S)-1-hydroxy-2-methylbutyl]-4-methylfuran-2(5H)-one, 4.22: 5-hydroxy-3-[(1S,2S)-1-hydroxy-2-methylbutyl]-4-methylfuran-2(5H)-one, 4.31: 3-[(1R)-1-hydroxy-2,2-dimethylpropyl]-4-methylfuran-2(5H)-one, 4.32: 3-[(1S)-1-hydroxy-2,2-dimethylpropyl]-4-methylfuran-2(5H)-one, 4.51: 3-(1-hydroxydecyl)-4-methylfuran-2(5H)-one a). a) Racemate b) Mixture of the two C(5)-epimers c) Mixture of the two C(1')-epimers d) Mixture of all four diastereoisomersC) commercially available flavoring compounds. 11: sotolone, 3-hydroxy-4,5-dimethylfuran-2(5H)-one; 12: emoxyfurane or EMF, 5-ethyl-3-hydroxy-4-methylfuran-2(5H)-one; 13: dihydroactinolide, 5,6,7,7a-4,4,7a-trimethyltetrahydrobenzofuran-2(4H)-one; 14: methyltetrahydrofuranone, 2-methyldihydrofuran-3(2H)-one;, 15: norfuraneol, 4-hydroxy-5-methylfuran-3(2H)-one; 16: DMHF or furaneol, 4-hydroxy-2,5-dimethylfuran-3(2H)-one; 17: pineapple ketone acteate, 2,5-dimethyl-4-oxo-4,5-dihydrofuran-3-yl acetate; 18: HF or homofuraneol; 5-ethyl-4-hydroxy-2-methylfuran-3(2H)-one; 19: methyl furyl butanal, 3-(5-methyl-2-furyl)butanal; 20: L-ascorbic acid, (5R)-3,4-dihydroxy-5-[(1S)-1,2-dihydroxyethyl]furan-2(5H)-one; 21: (5Z)-4-bromo-5-(bromomethylene)-3-butylfuran-2(5H)-one; 22: (5Z)-4-bromo-5-(bromomethylene)-3 [(1R)-1-hydroxybutyl]furan-2(5H)-one; 23: AHL, principal structure of N-acyl-L-homoserine lactones with N-decanoyl-L-homoserine lactone as example.