To simplify the calculations, the methyl ester groups in 15 and 18 were replaced by methyl groups (now: Me-15, Me-18). Due to the non-planar  ring geometry we calculated NICSzz values at various distances greater than 1.7 Å below the ring centroids to avoid contaminations of -bond-induced ring currents . These one-and two-dimensional NICSzz scans of Me-15 (Fig. ) reveal a pronounced diatropic ring current of the C(4) to C(9) fragment of Me-15 with NICS(1.8)zz values reaching down to -18.6 ppm. In contrast, the adjacent ring current in the C(2-4)⋅⋅⋅C (9-11) fragment is only moderately diatropic with less negative NICS(1.8)zz values of -12.5 ppm. In contrast, upon [1,11] sigmatropic rearrangement to 18, the diatropic ring currents are equalized over the 10 system of Me-18 with similar NICS(1.8)zz values of -11.3 ppm and -15.2 ppm for the six-and seven-membered fragments, respectively. Finally, the plotted ACID underscores the conjugation paths of the ring currents unambiguously (Fig. , f) . A significant homoaromatic through-space interaction for Me-15 can be observed between atoms C(2) and C(11) at a critical isosurface value (CIV) of 0.034 supporting a global 10π homoaromatic character in agreement with the NICS analysis of 15 (in comparison, the CIV for non-planar cycloheptatriene 1 is 0.027 at the same level of theory ). A second through-space interaction between C(4) and C( ) is observed at a CIV of 0.026 indicating a local 6π homoaromatic ring current in 15.