by Bumagin, Nikolai A., Sukhomlinova, Ludmila I., Luzikova, Elena V., Tolstaya, Tatiana P., Beletskaya, Irina P.
Published in Tetrahedron letters (05.02.1996)

by Tolstaya, Tatiana P., Tsariev, Dmitry A., Luzikov, Yury N.
Published in Tetrahedron letters (23.06.1997)