16-O-Demethyl Fusicoccin J and Its 3-Epimer fromFusicoccum amygdali, and Their Seed Germination-stimulating Activity in the Presence of Abscisic Acid

Abstract

Our search for new metabolites biosynthetically related to fusicoccin with potent plant growth-stimulating actiyity from the culture Mtrate of fusicoccum amJtgtinli F6 resulted in the isolation of a new deriyatiye of fusicoccin J, as well as fusicoccin J and 16-O-demethyl 3-epifusicoccifi J. Its structure was analyzed by 600 MHz NMR spectrometry and identified as 16-O-demethyl fusicoccin J. The biosynthetic relationships among 16-O-demethyl fusicoccin J and its 3-epimer, and f-sicoccin J are discussed in connection with the co-occurrence of both of the 3-epimers of 16-O-demethyl fusicoccin J. 16-O-Demethyl fusicoccin J alld its 3epimer showed oilly low germination-stimulatillg activity toward lettuce seeds in the presence of abscisic acid (20 "M), the latter being slightly mere actiye than the former.

(+)-Menthol and Its Hydroxy Derivatives, Novel Fungal Monoterpenols from the Fusicoccin-producing Fungi,Phomopsis amygdaliF6a and Niigata 2

“…Its relative stereochemistry has been elucidated, but its absolute conˆguration has not previously been determined. In our current eŠort to isolate new fusicoccins from the fungus, it was found that P. amygdali F6a 4) (the Italian strain) produced fusicoccin J together with new 16-O-demethylfusicoccin J, and that P. amygdali Niigata 2 5) (the Japanese strain) produced 3?-deacetylfusicoccin A together with new 3-epifusicoccins. 6) We also isolated (+)-menthol (1) as a novel fungal metabolite from the cultureˆltrate of the Niigata 2 strain, and its related metabolites, (+)-(1R,3S,4R,6S )-6-hydroxymenthol (3) as a new compound and (+)-(1S,3S,4R)-7-hydroxymenthol (2), and known 4 from a cultureˆltrate of the F6a strain (Fig.…”

“…Phomopsis ( Fusicoccum) amygdali F6a 4) was reciprocally shake-cultured for 4 days at 259 C in 500-ml Sakaguchi ‰asks, each containing 100 ml of an 8z sugar-0.5z peptone-1.0z corn steep liquor-0.5z NaCl medium. The cultureˆltrate (ca.…”

“…The EtOAc extract (1.76 g) was separated by silica gel ‰ash chromatography, using stepwise elution with CHCl3 W EtOH mixtures, to give three fractions (fractions 1 and 2 were eluted with a mixture of 40:1 CHCl3 W EtOH, and fraction 3 with a mixture of 30:1 CHCl3 W EtOH). Fraction 2 (310 mg) containing fusicoccin A 4) was further separated by a similar chromatographic procedure, employing a mixture of 3:1 n-hexane W acetone as the eluent. The eluates were collected in test tubes (8 ml each), and colorless crystals (3.1 mg, 3) that formed in the eluate were collected from tube numbers 14-15.…”

Novel Fusicoccins R and S, and the Fusicoccin S Aglycon (Phomopsiol) fromPhomopsis amygdaliNiigata 2-A, and Their Seed Germination-stimulating Activity in the Presence of Abscisic Acid

“…15) However, significant differences between them in the ½ D and chemical shift values (Á þ1:4-À1:9 ppm) of the 13 C-NMR signals (C-1, 5, 16, and 17 in Table 1) were apparent. In addition, careful irradiation at the 17-H signal of substance A did not produce any DIF-NOE signals of 16-H. 14) These observations suggested that substance A was the 3-epimer of O-demethylcotylenol. The stereochemistry of substance A was elucidated by DIF-NOE spectrometry, using a 600 MHz NMR spectrometer: DIF-NOEs in substance A were observed not only between 17-H and 9-H/4 -H ( 1.66), and 18-H and 9-H, but also between 6-H and 8-H/5 -H ( 1.90), and 16-H ( 3.40) and 5 -H/4 -H ( 1.79) (Fig.…”

“…Fraction 3 was rechromatographed by a similar method, using a 19:1 mixture of CHCl 3 /EtOH and then a 31:1 mixture of EtOAc/EtOH, to give fine colorless crystals (18 mg). Substances B and C were detected together with 16-O-demethyl-FC J 14) in fraction 4 (7:1 CHCl 3 / EtOH). These were separated by a similar method, using EtOAc/EtOH mixtures, to give 5 fractions.…”