βγ-Dehydrocurvularin and Related Compounds as Nematicides ofPratylenchus penetransfrom the FungusAspergillussp.

Curvularin‐Type Metabolites from the Fungus Curvularia sp. Isolated from a Marine Alga

“…More recently, the isolation of the known compound 11β-hydroxy-12-oxocurvularin (5a) was reported from the fungus Aspergillus sp. [22] On the basis of the identical NMR spectroscopic data we believe that the structure of curvulone A (1) had been erroneously determined earlier as 11β-hydroxy-12-oxocurvularin (5a) and thus the structure has to be revised to 1. The previously reported curvulone A, which was isolated together with curvularin deriva-tives having the 15S configuration, has a positive specific rotation {[α] D 25 = +41 (EtOH)}, [20] whereas our (10S,15R)-curvulone A (1) has a negative one {[α] D 25 = -76 (EtOH)} and identical spectroscopic data, which implies that they are probably enantiomers.…”

“…[10] Compound 4 ( Figure 1) was identified as the R enantiomer of the known α,β-dehydrocurvularin. Although the isolation of (10E,15S)-α,β-dehydrocurvularin has been reported from a number of fungal species such as Curvularia, [29,30] Stemphylium, [31] Penicillum, [3,7,21,27,28,32] Cochliobolus, [33] Aspergillus [6,22] and Alternaria, [34,35] there is only a single example of the isolation of (10E,15R)-α,β-dehydrocurvularin from the marine fungus Curvularia sp. [10] Although the absolute configuration of (10E,15S)-α,β-dehydrocurvularin has been determined unambiguously by total synthesis [36] and chemical correlation, [32] we intended to test our solid-state TD-DFT ECD spectroscopic method for its configurational assignment.…”

Fumiquinones A and B, Nematicidal Quinones Produced byAspergillus fumigatus

“…We have previously investigated such fungal metabolites as aspyrone, 1) peniprequinolone, 2) -dehydrocurvularin, 3) and penipratynolene 4) for their potential as nematicides against the root-lesion nematode, Pratylenchus penetrans, which is a parasite of many crop plants and causes root necrosis. 5,6) Japanese black pine (Pinus thunbergii Parl.)…”

Penipratynolene, a Novel Nematicide fromPenicillium bilaiaeChalabuda

“…We have previously investigated such fungal metabolites as aspyrone, 1) peniprequinolone, 2) penigequinolones 2) and 3-methoxy-4,6-dihydroxy-4-(4 0 -methoxyphenyl)quinolinone, 2) -dehydrocurvularin and related curvularines 3) for their potential as nematicides against the root-lesion nematode Pratylenchus penetrans, which is a parasite of many crop plants and causes root necrosis. [4][5][6][7] Our screening program for novel naturally occurring nematicides led to the investigation of the metabolites of Penicilium bilaiae Chalabuda.…”

“…In addition, 1 and 3 had more effective nematicidal activities than that of aspyrone as a positive control. [1][2][3] The nematicidal activities of 2-4 suggested that the carboxy groups in the molecule played an important role in this activity. The presence of acetylenic carbons may play an important role in nematicidal activity of 1, since many naturally occurring acetylene compounds are known as nematicidal substances.…”