Zinc iodide-catalyzed cycloaddition of furan to 1-cyanovinyl (1′S)-camphanate or 1-cyanovinyl (1′R)-camphanate led to optically pure (1R,2S,4R)-2-exo-cyano-7-oxabicyclo[2.2.1]-hept-5-en-2-yl (1S')-camphanate and (1S,2R,4S)-2-exo-cyano-7-oxabicyclo[2.2.1]hept-5-en-2-yl (1R')-camphanate, respectively. Saponification afforded (1R,4R)- and (1S,4S)-7-oxabicyclo[2.2.1]-hept-5-en-2-one, respectively, and allowing recovery of the chiral auxiliaries (1S)- and (1R)-camphanic acid, respectively. The 7-oxabicyclo[2.2.1]hept-5-en-2-yl derivatives (”naked sugars“) so-obtained can be substituted at C(3), C(5) and C(6) by direct techniques with high stereoselectivity. The methods exploit the exo-facial selectivity of the reactions of these bicyclic systems and the regiochemical control exerted by the remote substituents at C(2) in electrophilic attack at C(5) and C(6). The polysubstituted 7-oxabicyclo[2.2.1]heptan-2-ones so-obtained are chirons that can be converted into D- or L-hexose derivatives and analogues, into 2,5-anhydrohexonic acid derivatives (precursors for C-nucleosides and C-glycosides), or into polysubstituted cyclohex-1-ones. Moreover, conditions have been found under which the bicyclic ethers can transformed into (+) and (−)-methyl 8-epinonactate and (+)- and (−)-methyl nonactate (precursors of nonactine), into octoses, into branched carbohydrates such as calditoses and calditols, and into (+)-castanospermine. Compared with natural carbohydrates, the ”naked sugars“ are chirons with the following advantages: (1) the problem of selective protection and deprotection of polyalcoholic systems does not exist; (2) the functional moieties are grafted onto C(3), C(5), and C(6) of the 7-oxabicyclo[2.2.1]heptane systems together with the appropriate protective groups; (3) since both enantiomeric forms of the ”naked sugars“ an available, either enantiomers of a targeted compound can be reached with the equal ease.