Heteroatomic oligonucleoside linkages

Claim 1

A compound having structure: ##STR7## wherein: L 1 --L 2 --L 3 --L 4 is CR 1a R 1b --CR 2a R 2b --CR 3a R 3b --Z 4 , CR 1a R 1a --CR 2a R 2b --Z 3 --Z 4 , CR 1a R 1b --Z 2 --CR 3a R 3b --Z 4 , Z 1 --CR 2a R 2b --CR 3a R 3b --Z 4 , CR 1a R 1b --Z 2 --Z 3 --Z 4 , Z 1 --CR 2a R 2b --Z 3 --Z 4 or Z 1 --Z 2 --CR 3a R 3b --Z 4 ; Z 1 , Z 2 , Z 3 and Z 4 are, independently, O, NR 4 , S, SO, SO 2 , Se, P(═Y 1 )Y 2 or Si(R 6 ) 2 ; R 1a , R 1b , R 2a , R 2b , R 3a and R 3b are, independently, H, R 5 , O--R 5 , S--R 5 , NR 4 R 5 ; or, independently, together R 1a and R 1b , or R 2a and R 2b , or R 3a and R 3b are ═O; X is H, OH, O--R 5 , S--R 5 , NR 4 --R 5 , R 5 , F, Cl, Br, CN, CF 3 , OCF 3 , OCN, SOCH 3 , SO 2 CH 3 , ONO 2 , NO 2 , N 3 , aminoalkylamino, polyalkylamino or substituted silyl; Y 1 is O, S, Se, or NR 4 ; Y 2 is OH, OR 5 , SH, SR 5 , SeH, R 5 , BH 3 or NR 4 R 5 ; R 4 , R 5 and R 6 are, independently, one of: an electron pair of a multiple bond; H; straight or branched chain alkyl or substituted alkyl; straight or branched chain alkenyl or substituted alkenyl; straight or branched chain alkynyl or substituted alkynyl; 14 C-containing lower alkyl, lower alkenyl or lower alkynyl; substituted or unsubstituted alkaryl or aralkyl; 14 C-containing alkaryl or aralkyl; aryl; alicyclic; a reporter molecule; and where said substituents are OH, ═O, CO 2 H, O-alkyl, SH, S-alkyl, NH-alkyl, N-(alkyl) 2 , alkyl, F, Cl, Br, CN, CF 3 , OCF 3 , OCN, SOCH 3 , SO 2 CH 3 , ONO 2 , NO 2 , N 3 , NH 2 , aryl, aralkyl, sulfide, or silyl; Q is O or CH 2 ; n is an integer greater than 0; Bx is a variable heterocyclic base moiety; and said alkyl groups have 1 to 12 carbon atoms, said alkenyl and alkynyl groups have 2 to 12 carbon atoms, said alkaryl and aralkyl groups have 7 to 14 carbon atoms, and said aryl groups have 6 to 14 carbon atoms.