Coniferains C and D, New Eunicellin-Based Diterpenoids from Cladiella conifera

Abstract

Chemical examination of Cladiella conifera, collected in the waters of Taiwan, led to the isolation of two new eunicellin-based diterpenoids, coniferains C (1) and D (2). The structures of 1 and 2 were established by spectroscopic methods. Eunicellins 1 and 2 were found to promote cell viability in DLD-1 cells at a concentration of 20 μM.

Marine natural products

“…544 Two publications from the same research group described new xenicane diterpenes, coniferains A–D 1382 – 1385 , isolated from a Taiwanese collection of Cladiella conifera . 545,546 The structure of coniferain A matched that reported in 2010 for australin F, prompting reexamination of NMR data leading in turn to reassignment of the structure of the latter to 1386 . Litophynols C 1387 and D 1388 were isolated from a Ximao Island collection of Cladiella krempfi .…”

Cladiella Octocorals: Enormous Sources of Secondary Metabolites with Diverse Structural and Biological Properties

“…The anti‐inflammatory activity bioassay indicated that compound 93 suppressed the release of COX‐2 to 84.5±2.8 %, compared to the cells stimulated with LPS only at a concentration of 10 μM. The continuing study of this Formosan specimen yielded four new eunicellin‐based diterpenoids, namely, coniferains A−D ( 94 – 97 ) [41,42] . Their structures varied at the different linkages of the ether bridge and the degrees of oxygenation.…”