Synthetic heparin pentasaccharides

1. A pentasaccharide building block for the preparation of synthetic heparinoids, said building block being of General Formula I,

In which the configuration of the monosaccharidic units and the stereochemistry of the internal linkages is defined as D-gluco-alpha-1,4-D-glucurono-beta-1,4-D-Gluco-alpha-1,4-L-idurono-alpha-1,4-D-gluco, and the substituents are defined as;

X 1 is selected from the group consisting of hydroxy, C 2 to C 10 ; alkoxy; aryloxy, thioalkyl, thioaryl, imidoyl, t butyldiphenylsilyloxy; a lipoaminoacid or other such group suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta; or an alpha methoxy group;

R H ,R H1 and R H2 are benzyl;

R A is selected from the group consisting of an azido function, an NH-Dde, and NH-DTPM;

R S1 , R S2 and R S5 are independently selected from the group consisting of alkylacyl and arylacyl;

R S3 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S4 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R E1 is methyl;

R E2 is methyl;

R B is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R B1 is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R P1 is benzyl; and

R P2 is benzyl.

2. The pentasaccharide building block of claim 1 , wherein R S1 ,R S2 and R S5 are benzoyl.

3. The pentasaccharide building block of claim 1 , wherein R S1 ,R S2 and R S5 are benzoyl; and R S3 and R S4 are 4-methoxybenzyl.

4. The pentasaccharide building block of claim 1 , wherein R S3 and R S4 are 4-methoxyphenyl.

5. The pentasaccharide building block of claim 1 , wherein R S1 ,R S2 and R S5 are benzoyl; and R S3 and R S4 are 4-methoxyphenyl.

6. The pentasaccharide of claim 1 , wherein

X 1 is selected from the group consisting of alpha or beta thiomethyl, thiocresyl, t-butyldiphenylsilyloxy, and alpha methoxy.

7. A method of synthesizing the pentasaccharide of claim 1 , comprising the steps of forming a trisaccharide EDC of Formula II,

wherein:

X 2 is selected from thioalkyl, thioaryl, halogen, trichloroacetimidoyl, phosphate and related phosphate ester type leaving groups, n-pentenyl, and the stereochemistry may be alpha or beta;

R H is benzyl;

R H2 is benzyl;

R S3 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S4 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S5 is selected from the group consisting of alkylacyl and arylacyl;

R E1 is methyl;

R B is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R B1 is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R P1 is benzyl;

R P2 is benzyl;

and forming a disaccharide BA of Formula III

wherein:

X 1 is selected from the group consisting of C 2 -C 10 alkoxy, aryloxy, thioalkyl, thioaryl, t butyldiphenylsilyloxy a lipoaminoacid or other such group suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta, or an alpha methoxy group;

R H1 is benzyl;

R A is selected from the group consisting of an azido function, an NH-Dde, and NH-DTPM;

R S1 is selected from the group consisting of alkylacyl and arylacyl;

R S2 is selected from the group consisting of alkylacyl and arylacyl;

R Q is —(C═O)—OR E2 , wherein R E2 is methyl;

R L is H;

and linking the trisaccharide to the disaccharide to form the pentasaccharide.

8. The method of claim 7

wherein:

X 1 is selected from the group consisting of thiomethyl, thioethyl, thiocresyl, t butyldiphenylsilyloxy a lipoaminoacid suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta; or alpha methoxy;

R S1 , R S2 and R S5 are benzoyl;

R S3 is 4-methoxybenzyl;

R S4 is 4-methoxybenzyl; and

X 2 is selected from thiomethyl, thiocresyl, and trichloroacetimidoyl, and the stereochemistry may be alpha or beta.

9. A method of synthesizing the pentasaccharide of claim 1 , comprising the step of synthesizing a tetrasaccharide EDCB (Formula IV),

wherein:

X 2 is selected from a thioalkyl, thioaryl, halogen, trichloroacetimidoyl, phosphate and related phosphate ester type leaving groups, and the stereochemistry may be alpha or beta;

R H , and R H2 are benzyl;

R S2 and R S5 are independently selected from the group consisting of alkylacyl and arylacyl;

R S3 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S4 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R E1 is methyl;

R E2 is methyl;

R B is selected from the group consisting of an azido function, an NH-Dde and NH-DTPM group;

R B1 is selected from the group consisting of an azido function, an NH-Dde and NH-DTPM group;

R P1 is benzyl; and

R P2 is benzyl;

and linking the tetrasaccharide to a monosaccharide of Formula V

wherein:

X 1 is selected from C 2 -C 10 alkoxy, aryloxy, t butyldiphenylsilyloxy; a lipoaminoacid suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta; or an alpha methoxy group;

R H1 is benzyl;

R A is selected from the group consisting of an azido function, an NH-Dde, and NH-DTPM; and

R S1 is independently selected from the group consisting of alkylacyl and arylacyl.

10. The method of claim 9 wherein:

X 1 is selected from the group consisting of t butyldiphenylsilyloxy, a lipoaminoacid suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta; or an alpha methoxy group;

R S1 , R S2 and R S5 are benzoyl;

R S3 is 4-methoxybenzyl;

R S4 is 4-methoxybenzyl; and

X 2 is selected from thiomethyl, thiocresyl, and trichloroacetimidoyl, and the stereochemistry may be alpha or beta.

11. A method of synthesizing the pentasaccharide of claim 1 , comprising synthesizing a tetrasaccharide DCBA of Formula VI

wherein:

X 1 is selected from the group consisting of C 2 to C 10 alkoxy, aryloxy, thioalkyl, thioaryl, t butyldiphenylsilyloxy; a lipoaminoacid or other such group suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta, or an alpha methoxy group,

R H is benzyl;

R H1 is benzyl;

R A is selected from the group consisting of an azido function, an NH-Dde, and NH-DTPM;

R S1 is alkylacyl or arylacyl;

R S2 is alkylacyl or arylacyl;

R S3 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S4 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R E1 is methyl;

R E2 is methyl;

R B is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R P1 is benzyl;

R P2 is benzyl;

and linking the tetrasaccharide to a monosaccharide of Formula VII

wherein:

X 2 is selected from a thioalkyl, thioaryl, and trichloroacetimidoyl; and the stereochemistry may be alpha or beta;

R S5 is selected from the group consisting of alkylacyl and arylacyl;

R H is benzyl;

R H2 is benzyl;

R B1 is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group.

12. The method of claim 11 , wherein:

X 1 is selected from the group consisting of thiomethyl, thioethyl, thiocresyl, t butyldiphenylsilyloxy a lipoaminoacid suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta, or an alpha methoxy group;

R S1 , R S2 and R S5 are benzoyl;

R S3 is 4-methoxybenzyl;

R S4 is 4-methoxybenzyl; and

X 2 is selected from thiomethyl, thiocresyl, and trichloroacetimidoyl, and the stereochemistry may be alpha or beta.

13. A method of synthesizing the pentasaccharide of claim 1 , comprising the steps of forming a disaccharide ED of Formula VIII,

wherein: X 2 is selected from thioalkyl, thioaryl, trichloroacetimidoyl, phosphate and related phosphate ester type leaving groups, and the stereochemistry may be alpha or beta;

R S5 is alkylacyl or arylacyl;

R H is benzyl;

R H2 is benzyl;

R B1 is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R E1 is methyl;

R P1 is benzyl;

R P2 is benzyl;

and forming a trisaccharide CBA of Formula IX

wherein:

X 1 is selected from the group consisting of C 2 to C 10 alkoxy, aryloxy, thioalkyl, thioaryl, t butyldiphenylsilyloxy; a lipoaminoacid or other such group suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta, or an alpha methoxy group;

R B is selected from the group consisting of an azido function, an NH-Dde and an NH-DTPM group;

R A is selected from the group consisting of an azido function, an NH-Dde, and NH-DTPM;

R S1 and R S2 are independently selected from the group consisting of alkylacyl and arylacyl;

R S3 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R S4 is selected from the group consisting of 4-methoxyphenyl and 4-methoxybenzyl;

R H is benzyl;

R H1 is benzyl; and

R E2 is methyl;

and linking the disaccharide to the trisaccharide.

14. The method of claim 13 wherein:

X 1 is selected from the group consisting of thiomethyl, thioethyl, thiocresyl, t butyldiphenylsilyloxy a lipoaminoacid suitable for conjugation to delivery systems or solid supports; and the stereochemistry may be alpha or beta, or an alpha methoxy group;

R S1 , R S2 and R S5 are benzoyl;

R S3 is 4-methoxybenzyl;

R S4 is 4-methoxybenzyl; and

X 2 is selected from thiomethyl, thiocresyl, and trichloroacetimidoyl, and the stereochemistry may be alpha or beta.