R 3 3 7 July 8, 2019 16 32 64 128 3r r 3 3 7r R )- 3 3 5 7 tetramethyloctane 5r =- 3 r 3 )- 7 3 r − 7 3 9 R 3 7 R(3 3 3) R - 3
