... Volume 24, Issue 21, 1983, Pages 2213-2216. ... Download full text in PDF. Tetrahedron Letters,Vo1.24,No.21,pp 2213-2216,1983 0040-4039/83/212213-04$03.00/0 Printed in Creat Britain ... N ~N~ 17 18 I ~+ I~ CH,OHI \ \ CHO ~O 19 20 21 IFI,OH ' I + / ICHO s,'1 \ CU 22 23 24 I \ ...