Thus, we moved to DFT calculations to substantiate our hypothesis. We computed the Boltzmann populations of 6, 7, 8, 1, and the hypothesized 1R,10R-microeunicellene (1R,10R-1) (Fig. , Extended Data Figs. exhibits less flexibility, with its conformational space primarily populated by two conformers, accounting for 96.3% of the total space. The approximate ratio of these conformers is 7.4:2.2. In the case of 1, a single conformation overwhelmingly dominates the conformational space, representing 99.3% of the total space (Fig. , Extended Data Fig. ). This finding further confirms that 1 adopts a predominant conformation. Additionally, the calculated results of the hypothesized 1R,10R-1 align with those for 1, suggesting that the trans configuration of C1 and C10, regardless of the absolute orientations, has the same effect on flexibility (Extended Data Fig. ).