Boronated protoporphyrins

Fig. 8. Boronated protoporphyrin (BOPP). The closed circles represent B-H groups and the open circles represent CH or C groups...

Boronated protoporphyrin (2,4-(a,/Tdihydroxyethyl)deuteroporphyrin IX, BOPP, Fig. 8), a neutron capture agent, localizes in cerebral gliomas with a ratio of 400 1 as compared with normal brain tissue [116]. The manganese(III) complex of BOPP was investigated as a MRI contrast agent in the expectation that it would behave similarly to the free base BOPP and would act in the dual role of tumor detector and radiation sensitizer [117]. The 1 value for Mn-BOPP at... 

Hill et al. were the first to report an interesting approach to combine PDT with boron neutron capture therapy (BNCT) and later studied the selective tumor uptake of a boronated protoporphyrin 6 in mice bearing an implanted intracerebral glioma. TTiey found this compound to be selectively localized in tumor at ratios as high as 400 1 relative to normal brain, indicating that this compound may be used as a potential drug for PDT and boron neutron capture therapy (BNCT). Another approach to overcoming the problem of HpD s chemically complex nature was the use of pure porphyrins such as isohematoporphyrin 7 and... 

---