Rhodamine derivatives for photodynamic therapy of cancer and in vitro purging of the leukemias
US5773460A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 1, 1996 |
| Grant date | Jun 30, 1998 |
| Priority date | — |
| Expiry date | Jul 1, 2016 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA61K41/0057
- WIPO fieldPharmaceuticals
- WIPO sectorChemistry
Abstract
The present invention relates to novel photoactivable rhodamine derivatives for enhancing high quantum-yield production and singlet oxygen generation upon irradiation with light while maintaining desirable differential retention of rhodamine between normal and cancer cells. Representative derivatives are 2-(4,5-dibromo-6-amino-3-imino-3H-xanthen-9-yl)-benzoic acid methyl ester hydrochloride; 2-(4, 5-dibromo-6-amino-3-imino-3H-xanthen-9-yl)-benzoic acid ethyl ester hydrochloride; 2-(4,5-dibromo-6-amino-3-imino-3H-xanthen-9-yl)-benzoic acid octyl ester hydrochloride; 2-(4,5-dibromo-6-amino-3-imino-3H-xanthen-9-yl)-benzoic acid n-butyl ester hydrochloride; 2-(6-ethyl amino-3-ethyl imino-3H-xanthen-9-yl)-benzoic acid n-butyl ester hydrochloride; and photoactivable derivatives thereof. These derivatives are utilized in an amount to achieve appropriate intracellular levels of the derivative when irradiation of a suitable wavelength and intensity is applied to photoactivate the derivative and thereby induce cell killing.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.