lengths range from 1.838(1) to 1.872(3) and from 1.771 (3) to 1.794(4)Å, respectively. The axial O–S–O and equatorial Car–S–Car bond angles lie in the narrow intervals of 174.9(2)–177.4(4)° and 105.8(2)–106.9(2)°, respectively. The five-membered spirorings are practically planar in 1–3. The six-membered spirorings in 2 and 4 assume distorted sofa conformations. The seven-membered spiroring in 3, having four