Compound according to the formula: wherein R1 is selected from, wherein: R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; with the proviso that if R1 is [formula B], R2, R3 and R5 are hydrogen and X is hydroxyl R4 is not methoxy; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, or halogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, or (C 1 to C 5) alkoxy; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; with the proviso that if R1 is [formula B], R2, R3 and R5 are hydrogen and X is hydroxyl R4 is not methoxy; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, or azido(C 1 to C 4)alkyl; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, formyloxy, acetoxy, or nitrooxymethyl,; or a pharmaceutically acceptable salt thereof for use as a medicament; where alkyl includes a straight, branched or cyclic alkyl group. R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; with the proviso that if R1 is [formula B], R2, R3 and R5 are hydrogen and X is hydroxyl R4 is not methoxy; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, or halogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, or (C 1 to C 5) alkoxy; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; with the proviso that if R1 is [formula B], R2, R3 and R5 are hydrogen and X is hydroxyl R4 is not methoxy; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, or azido(C 1 to C 4)alkyl; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, hydroxy, formyloxy, acetoxy, nitrooxy, nitrooxymethyl, or a halogen; or a pharmaceutically acceptable salt thereof for use as a medicament or R2 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, (C 2 to C 4) alkenyl or alkynyl, azido(C 1 to C 4)alkyl, or hydrogen; R3 is (C 1 to C 5) alkyl, (C 1 to C 3) alkyl with 1 to 3 halogen substituents, halogen or hydrogen; R4 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, or hydrogen; R5 is (C 1 to C 5) alkyl, (C 1 to C 5) alkoxy, acetoxy, halogen or hydrogen; X is OTBS, formyloxy, acetoxy, or nitrooxymethyl,; or a pharmaceutically acceptable salt thereof for use as a medicament; where alkyl includes a straight, branched or cyclic alkyl group.