[Structure: see text]. Citrinadin A (2) is a pentacyclic indolinone alkaloid isolated from the cultured broth of a fungus, Penicillium citrinum, which was separated from a marine red alga. The absolute stereochemistry of the pentacyclic core in 2 and its new congener, citrinadin B (1), was elucidated by analysis of the ROESY spectrum for the chlorohydrin derivative (3) of 1 as well as comparison of the electronic circular dichroism (ECD) spectra for 1 and 2 with those of known spirooxiindole alkaloids. On the other hand, the absolute configuration at C-21 bearing an epoxide ring was assigned as S by comparison of the vibrational circular dichroism (VCD) spectra of 1 with those of model compounds 2S- and 2R-2,3-epoxy-3,3-dimethyl-1-phenylpropan-1-one (4a and 4b, respectively).

Two new 10-membered macrolides, modiolides A (1) and B (2), and a new linear pentaketide, modiolin (3), were isolated from the cultured broth of a fungus Paraphaeosphaeria sp. (N-119), which was separated from a marine horse mussel, and the structures were elucidated by spectroscopic data.

Three new pyrrolidine alkaloids, scalusamides A-C (1-3), were isolated from the cultured broth of the fungus Penicillium citrinum, which was separated from the gastrointestine of a marine fish, and the structures were elucidated by spectroscopic data. The absolute stereochemistry of C-2 in the pyrrolidine unit was determined by HPLC analysis of a Marfey's derivative of the hydrolysate of 1, while that of 2 and 3 was assigned by comparison of spectroscopic data of 3 and reductive products of 1 and 2. On the other hand, each of 1-3 was found to be a mixture of epimers at C-7. Scalusamide A (1) exhibited antifungal and antibacterial activities.

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Alkaloids Alkaloids U 0600 Speradine A, a New Pentacyclic Oxindole Alkaloid from a Marine-Derived Fungus Aspergillus tamarii. -(TSUDA, M.; MUGISHIMA, T.; KOMATSU, K.; SONE, T.; TANAKA, M.; MIKAMI, Y.; SHIRO, M.; HIRAI, M.; OHIZUMI, Y.; KOBAYASHI*, J.; Tetrahedron 59 (2003) 18, 3227-3230; Grad. Sch. Pharm. Sci., Hokkaido Univ., Sapporo 060, Japan; Eng.) -Steudel 34-194

Absolute Stereochemistry of Citrinadins A (Ia) and B (Ib) from Marine-Derived Fungus. -(MUGISHIMA, T.; TSUDA, M.; KASAI, Y.; ISHIYAMA, H.; FUKUSHI, E.; KAWABATA, J.; WATANABE, M.; AKAO, K.; KOBAYASHI*, J.; J. Org. Chem. 70 (2005) 23, 9430-9435; Grad. Sch. Pharm. Sci., Hokkaido Univ., Sapporo 060, Japan; Eng.) -Jannicke 13-201