{TAIL ~ Reduction} of lactones 1, which were prepared by the previously disclosed methods , with DIBAL H followed by {HEAD ~ acid catalyzed methylation} provides lactal intermediates 2 
{ TAIL ~ Reduction } of lactones 1 , which were prepared by the previously disclosed methods , with DIBAL H followed by { HEAD ~ acid catalyzed methylation } provides lactal intermediates 2
TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH