Dedicated to our friend and colleague Prof. Antonio Togni on the occasion of his 65th birthday: N. V. Stoletova, A. D. Moshchenkov, A. F. Smol’yakov, Z. T. Gugkaeva, V. I. Maleev, D. Katayev, V. A. Larionov, HelvChimActa 2021104, e2000193