Proline‐Containing Dipeptides from a Marine Sponge of a Callyspongia Species

Abstract

A detailed analysis of the chemical constituents of a marine sponge of Callyspongia sp. was performed. A new proline-containing dipeptide, callyspongidipeptide A (cyclo-((S)-Pro-8-hydroxy-(R)-Ile); 1) along with cyclo-((S)-Pro-(R)-Leu) (3) and seco-((S)-Pro-(R)-Val) (2) were isolated. The structures were determined on the basis of NMR and MS analysis, and the absolute configuration was determined by comparison of the optical rotation with known compounds.Introduction. -Marine sponges produce numerous bioactive compounds with promising pharmaceutical properties. The genus Callyspongia (order Haplosclerida, family Callyspongiidae) is widely distributed and contains various bioactive constituents such as polyacetylenes [1 -11] properties. In the course of our search for cytotoxic metabolites from marine sponges, we have discovered a new proline-containing dipeptide named callyspongidipeptide A (1) from Callyspongia sp., together with the new natural product seco-((S)-Pro-(R)-Val) (2) and the known compound cyclo-((S)-Pro-(R)-Leu) (3). The gross structures of these compounds were elucidated by the aid of COSY, HMQC, and HMBC experiments, while the absolute configuration was determined from the optical rotation. Here, we present the isolation and structure elucidation of these metabolites.

Lactococcus lactis KR-050L inhibit IL-6/STAT3 activation

“…; Yang et al . ). In the NMR spectra, the peaks of C‐10, H‐6 and H‐9 were observed in compounds 10 ( δ c 38·7 (C‐10) and δ H 4·12, 4·02 (H‐6 and 9)) and 11 ( δ c 42·7 (C‐10) and δ H 4·07, 3·92 (H‐6 and 9)) in CDCl 3 (Table ).…”

“…Synthetically, compared with the reference data, compounds 12 and 13 were identified as Cyclo‐( l ‐Pro‐ d ‐Ile) (Yang et al . ) and Cyclo‐( d ‐Pro‐ l ‐Ile) respectively (He et al . ) (Fig.…”

Marine natural products

“…Compounds 458 and 459 were generally cytotoxic, while 458 was also active against Leishmania major. 438 Citronamides A 463 and B 464, isolated from Citronia astra (Day Reef, Queensland, Australia), were moderately active against S. cerevisiae (baker's yeast). 431 Total synthesis 432 has established the absolute configuration of tedanalactam 460 (Tedania ignis), 433 and syntheses of bengazoles C and E (Jaspis sp.)…”

Metabolomic profiling and biological investigation of the marine sponge‐derived bacterium Rhodococcus sp. UA13

“…RV163, whereas that at m/z 226.132 [M‐H] − for the suggested molecular formula C 11 H 18 N 2 O 3 was dereplicated as callyspongidipeptide A. This peptide was isolated before from the marine sponge Callyspongia sp . Moreover, the mass ion peak at m/z 278.152 [M‐H] − , corresponding to the predicted molecular formula C 16 H 22 O 4 , was identified as oncorhyncolide, an antibacterial lactone earlier obtained from the phylum Actinobacteria MK157 .…”