TETRAHEDRON LETTERS, cilt.37, sa.16, ss.2821-2824, 1996 (SCI-Expanded)
Reaction of 1,8-diketones 3 with Lawesson's reagent 8 resulted in the formation of five and six-membered rings 5-7, 18, depending on the nature of the substituents. Product 6 is converted in two steps to the unsymmetric 'ET' analogue 20, containing an extra double bond. Copyright (C) 1996 Elsevier Science Ltd