Tamoxifen derivatives

Claim 2

3- and 4-iodotamoxifen derivatives which are compounds of formula (3) wherein the iodo substituent is present in the 3- or 4-position and Ri and R 2 , which may be the same or different, represent C 1 - 3 alkyl groups or R 1 represents a hydrogen atom and R2 a C 1 - 3 alkyl group or R1 and R 2 together with the nitrogen atom to which they are attached represent a saturated heterocyclic group and their pharmaceutically acceptable acid addition salts.

Claim 3

lodotamoxifen derivatives according to Claim 1 wherein R 1 and R 2 represent methyl groups or R 1 and R2 together with the said nitrogen atom represent a pyrrolidino group.

Claim 4

lodotamoxifen derivatives according to Claim 2 wherein the iodo substituent is in the 4- position.

Claim 5

lodotamoxifen derivatives according to Claim 1, 2 or 3 wherein the iodine atom is non-radioisotopic.

Claim 6

lodotamoxifen derivatives according to Claim 1, 2, 3 or 4 for use in treatment of estrogen receptor-positive breast cancer.

Claim 7

lodotamoxifen derivatives according to Claim 1, 2 , 3 or 4 for use in the preparation of a medicament for treatment of estrogen receptor-positive breast cancer.

Claim 8

A pharmaceutical composition comprising an iodotamoxifen derivative according to Claim 1, 2, 3 or 4, in association with a pharmaceutically effective diluent, carrier or excipient.

Claim 9

lodotamoxifen derivatives according to Claim 1, 2 or 3 wherein the iodine atom comprises 1251.

Claim 10

Radioisotopiciodotamoxifen derivatives according to Claim 1, 2, 3 or 8 for use in the preparation of a medicament for treatment of estrogen receptor-positive breast cancer.

Claim 11

Radioisotopiciodotamoxifen derivatives according to Claim 1, 2 or 3, wherein the iodine atom comprises 1231 or 131 I, for use in preparation of a formulation for gamma-ray photographic imaging of estrogen receptor-positive breast tumours.

Claim 12

A process for the preparation of an iodotamoxifen derivative according to Claim 1 wherein the iodine atom is radioisotopic, said process comprising reacting a compound of formula wherein R1 and R2 are as defined in connection with formula (3) and Y represents a 3- or 4- substituent capable of being cleaved from its benzene ring (including within this definition a non-radioisotopic iodine atom), with a reagent capable of effecting such cleavage and with a source of radioisotopic iodine.

Claim 13

A process according to Claim 11 wherein Y is chloro, bromo or iodo.

Claim 14

A process according to Claim 11 asor 12 wherein the cleavage-effecting reagent is an alkyllithium, the source of radioisotopic iodine is radioisotopic molecular iodine and the reaction is carried out in inert atmosphere.

Claim 15

A process according to Claim 11 wherein Y is non-radioisotopic iodo, the cleavage-effecting reagent is a copper salt and the source of radioisotopic iodine is radioisotopic sodium iodide.