Confirmation of the connectivity of 4,8,12,16,20-pentamethylpentacosylphoshoryl beta-D-mannopyranoside, an unusual beta-mannosyl phosphoisoprenoid from Mycobacterium avium, through synthesis.

The synthesis of the title glycolipid is reported. Comparison of the electrospray and high-energy collision-induced dissociation mass spectra of the synthetic material with those reported for the isolate confirm the structure of this unusual antigenic substance with its modified isoprenoid chain.