Labdanic diterpenoids represent an important group of natural products with relevant biological activities. One of the most known compounds of this series is forskolin – a secondary metabolite isolated from Coleus forskohlii plant and showing a myriad of therapeutic activities [1]. A lot of work has been done on the chemical synthesis of this remarkable compound and diverse strategies have been demonstrated for its total and semisynthesis by multiple step synthetic transformations [2]. On the other hand, elaboration of simpler analogs of forskolin on the basis of readily available manoyl oxides can be an alternative avenue towards compounds with similar activities.Reagents and conditions: ICH2CO2Et, DLP, Ph-H, 9 hrs. reflux. The current work presents the first results on the application of the radical addition methodology for the simultaneous attachment of a C2 synthon and a functional group to the lateral chain of both manoyl oxide and 13-epi-manoyl oxide, according to the described procedures [3]. Treatment of manoyl oxide with ethyl iodoacetate in presence of dilauroyl peroxide (DLP) led to the main reaction product 1, which is expected in accordance to the suggested free radical alkylation mechanism (scheme below). Surprisingly, a minor alkylated compound which lacks the iodine in its structure was also isolated. Its structure 2 represents a product of 1,5-radical migration, followed by elimination of hydrogen iodide. The 13-epimanoyl oxide reacted under similar conditions to provide a mixture of epimeric iodides 3 as basic products. We have also observed an unprecedented triple sequence of 1,5-radical migrations to the distal gem-dimethyl group in 4 leading to a remote functionalization. Acknowledgements The presented work was performed within the project “Radical mediated modifications of natural products” supported financially by the Swiss National Science Foundation (SCOPES program, project No. IZ73Z0_152346/1). References 1. Dewick, P. M. (2009) Medicinal Natural Products (3rd ed.), John Wiley & Sons, Ltd, Chichester. 2. Bhat, S. V. (1993) Forskolin and Congener, in Progress in the Chemistry of Organic Natural Products. Springer-Verlag, New York. pp. 1-74. 3. Ollivier, C., Bark, T., Renaud, P. (2000) An Efficient and Practical Tin Free Procedure for Radical Iodine Atom Transfer Reactions, Synthesis, 11, 1598–1602.