The biotransformation of the clerodane diterpene, 3,12-dioxo-15,16-epoxy-4-hydroxy-cleroda-13(16),14-diene (1), obtained from Croton micans var. argyroglossum (Baill.) Müll., was investigated for the first time. Whole cells of Cunninghamella echinulata and Rhizopus stolonifer were used as enzymatic systems, and with both fungi the only biotransformation product obtained was the new ent-neo-clerodane diterpene (3R,4S,5S,8S,9R,10S)-3,4-dihydroxy-15,16-epoxy-12-oxo-cleroda-13(16),14-diene (2a). The absolute stereochemistry of 2a was inferred by comparison of its optical rotation with those of the chemical reduction product of 1 and its quasienantiomer 2c.
BorgesK.B., BorgesW.S., Durán-PatrónR., PupoM.T., BonatoP.S., ColladoI.G. (2009) Stereoselective biotransformations using fungi as biocatalysts. Tetrahedron: Asymmetry, 20, 385–397.
2.
NunesF.M., SantosG.F., SaraivaN.N., TrappM.A., de MattosM.C., OliveiraM.C.F., Rodrigues-FilhoE. (2013) New fungi for whole-cell biotransformation of carvone enantiomers. Novel p-menthane-2,8,9-triols production. Applied Catalysis A, 468, 88–94.
3.
FurtadoR.A., GunaherathGmkb, BastosJ.K., GunatilakaA.A.L. (2013) Microbial biotransformation of 16a,17-epoxy-ent-kaurane-18-oic acid by Beauveria sulfurescens ATCC 7159-F. Natural Product Communications., 8, 1041–1044.
4.
MessianoG.B., WijeratneE.M.K., LopesL.M.X., GunatilakaA.A.L. (2010) Microbial transformations of aryltetralone and aryltetralin lignans by Cunninghamella echinulata and Beauveria bassiana. Journal of Natural Products, 73, 1933–1937.
5.
ChoudharyM.I., MohammadM.Y., MusharrafS.G., OnajobiI., MohammadA., AnisI., ShahM.R., Atta-Ur-Rahman. (2013) Biotransformation of clerodane diterpenoids by Rhizopus stolonifer and antibacterial activity of resulting metabolites. Phytochemistry, 90, 56–61.
6.
LammA.S., ReynoldsW.F., ReeseP.B. (2006) Bioconversion of Stemodia maritima diterpenes and derivatives by Cunninghamella echinulata var. elegans and Phanerochaete chrysosporium. Phytochemistry, 67, 1088–1093.
7.
HeX., ZengX., HuH., WuY. (2010) Cytotoxic biotransformed products from andrographolide by Rhizopus stolonifer ATCC 12939. Journal of Molecular Catalysis B: Enzymatic, 62, 242–247.
8.
FrijaL.M.T., FradeR.F.M., AfonsoC.A.M. (2011) Isolation, chemical, and biotransformation routes of labdane-type diterpenes. Chemical Reviews, 111, 4418–4452.
9.
MonteF.J.Q., DantasE.M.G., Braz-FilhoR. (1988) New diterpenoids from Croton argyrophylloides. Phytochemistry, 27, 3209–3212.
10.
KrebsH.C., RamiarantsoaH. (1996) Clerodane diterpenes and other constituents of Croton hovarum. Phytochemistry, 41, 561–563.
11.
GraikouK., AligiannisN., SkaltsounisA-L, ChinouI., MichelS., TillequinF., LitaudonM. (2004) New diterpenes from Croton insularis. Journal of Natural Products, 67, 685–688.
12.
GatlingS.C., JacksonJ.E. (1999) Reactivity control via dihydrogen bonding: diastereoselection in borohydride reductions of α-hydroxyketones. Journal of the American Chemical Society, 121, 8655–8866.
13.
FragaB.M., HernándezM.G., GonzálezP., LópezM., SuárezS. (2001) Biotransformation of the diterpene ribenone by Mucor plumbeus.Tetrahedron.57, 761–770.
14.
García-GranadosA., JiménezM.B., MartínezA., ParraA., RivasF., AriasJ.M. (1994) Chemical-microbiological synthesis of ent–13-epi-manoyl oxides with biological activities. Phytochemistry, 37, 741–747.
15.
WeckertE., HummerK., Addae-MensahI., AchenbachH. (1992) The absolute configuration of chiromodine. Phytochemistry, 31, 2170–2172.
16.
TokoroyamaT. (2000) Synthesis of clerodane diterpenoids and related compounds - stereoselective construction of the decalin skeleton with multiple contiguous stereogenic centers. Synthesis, 5, 611–633.
17.
WangX-N, BashyalB.P., WijeratneE.M.K., U'RenJ.M., LiuM.X., GunatilakaM.K., ArnoldA.E., GunatilakaA.A.L. (2011) Smardaesidins A–G, isopimarane and 20-nor-isopimarane diterpenoids from Smardaea sp., a fungal endophyte of the moss Ceratodon purpureus. Journal of Natural Products, 74, 2052–2061.
