Bioactive Terpenoids from Octocorallia, I. Bioactive Diterpenoids: Litophynols A and B from the Mucus of the Soft Coral Litophyton sp.

Abstract

Two new eunicellin-type diterpenoids, litophynols A [1] and B [2], and the known diterpenoids litophynins E [3], H [11], and I monoacetate [12], were isolated from the mucus secreted by the soft coral Litophyton sp. Their structures have been elucidated on the basis of spectral and single crystal X-ray analyses. These compounds have hemolytic activity.

Terpenoids from Marine Organisms: Unique Structures and their Pharmacological Potential

“…Indeed, several years later, eunicellin based diterpenes, like e.g. litophynol A (6) were isolated from a Japanese Litophyton species which showed ichthyotoxic and hemolytic activities (Miyamoto et al, 1994).…”

Furanocembranoids from the Soft Corals Sinularia asterolobata and Litophyton arboreum

“…-Soft corals contain a fairly large variety of secondary metabolites, mainly cembrane diterpenes, furanocembranoid diterpenes, norditerpenes, and furanosesquiterpenes [1 -5]. Many of these constituents are structurally unique and exhibit interesting biological activities, e.g., antiproliferative and cytotoxic activity toward various cancer cell lines [6 -9], inhibition of nicotinic acetylcholine receptors [10] and of insect growth [11], haemolytic activity [12], and ichthyodeterrence [13]. Two norfuranocembranoids 9 and 10 from the soft coral Sinularia scabra [6], and the norfuranocembranoid dimer singardin [9] from the soft coral Sinularia gardineri showed cytotoxic activity against the cell lines KB (human oral epidermoid carcinoma), Hepa59T/VGH (human liver carcinoma), P-388 (murine lymphocytic leukaemia), A-549 (human lung carcinoma), HT-29 (human colon carcinoma), and MEL-28 (human melanoma).…”

Bioactive Eunicellin-Based Diterpenoids from the Soft Coral Cladiella krempfi

“…The location of a n -butyrate at C-3 was then deduced by the chemical shifts of C-3 ( δ 86.0) and H 3 -15 ( δ 1.47). From the above results, the structure of compound 1 was shown to be highly related to that of a known compound, litophynol B ( 5 ) [16]. …”

“…also afforded diterpenes of this type [15]. Recently, our investigation on the chemical constituents of the Formosan soft coral Cladiella krempfi yielded four new eunicellin-type metabolites, krempfielins A–D ( 1 – 4 ), along with two known eunicellin-based diterpenoids, litophynol B ( 5 ) [16] and (1 R* , 2 R* , 3 R* , 6 S* , 7 S* , 9 R* , 10 R* , 14 R* )-3-butanoyloxycladiell-11(17)-en-6,7-diol ( 6 ) [17] (Chart 1). These compounds possess the more common C-2–C-9 ether linkage characteristic of the eunicellin-based diterpenoids.…”