Penitol A and Penicitols E–I: Citrinin Derivatives from Penicillium citrinum and the Structure Revision of Previously Proposed Analogues

Pitfalls in the structural elucidation of small molecules. A critical analysis of a decade of structural misassignments of marine natural products

“…The overall prole of d C values strongly favoured the revised structure 135 for penicitol A. 165 The bislactone aza-limonoid (+)-granatumine A (138) (Fig. 26), isolated from a Chinese mangrove, showed…”

“…25), was re-isolated from a coral-derived fungus ( P. citrinum ). 165 The X-ray analysis of 136 and 137 showed that due to a different conformation of the central pyrane ring, H-1 and H-14 were spatially close in both a cis - and a trans -relationship (2.30 Å and 2.88 Å, respectively) (Fig. 25).…”

Sinudenoids A–E, C19-Norcembranoid Diterpenes with Unusual Scaffolds from the Soft Coral Sinularia densa

“…The large coupling constants (J 4 , 12 = 10.5 Hz) indicated an anti orientation of H-4 and H-12. 19 The NOESY correlation from H-16 to H-12, along with the correlations from H-4 to H-2a (δ H 1.79) and OH-5 (δ H 4.22) and from H-1 to H-13b (δ H 2.79) and H-2a (δ H 1.79) in the 1D NOE difference spectra, indicated H-13b, H-1, H-4, and OH-5 are on the same side. Finally, the absolute configuration of 2 was unambiguously determined as 1R,4R,5S,9S,10R,11R,12R [Flack parameter of 0.04 (7)] by a single-crystal X-ray diffraction experiment with Cu Kα radiation (Figure 4).…”

Secondary Metabolites from Coral-Associated Fungi: Source, Chemistry and Bioactivities

“…Moreover, 307 showed cytotoxic activity against A549 and BEL-7402, with IC 50 values of 19 and 17 μM, respectively. Compounds 302 and 307 displayed antibacterial activity against S. aureus , B. subtilis , and Vancomycin-resistant E. faecalis 1010798 (VRE), with MIC values of 16, 32, 32 and 64, 32, 32 μM, respectively [ 142 ]. A new polyphenol, talaversatili A ( 308 ), was isolated from a soft coral-derived fungus Talaromyces sp.…”