Biomedical subjects
Publications and source records attributed to Ulrich Griesbach.
Substituted phenols were anodically coupled to the corresponding 2,2'-biphenols via tetraphenoxy borate derivatives. This electrochemical method is particularly useful for methyl-substituted substrates, such as 2,4-dimethyl phenol. The selective ortho-coupling reaction can be easily performed on a multikilogram scale.
The synthesis of the novel unprotected carboranyl C-glycosides 2 and 20-24 starting from ethynyl C-glycosides 1, 5-8, 10, and 13 is described. The new compounds are highly water-soluble and display only a very low cytotoxicity, which makes them promising candidates for use in boron neutron capture therapy for the treatment of cancer.
The synthesis and biological evaluation of two ortho-carborane derivatives which contain a 5,6,7-trimethoxyindole (TMI) unit for use in boron neutron capture therapy is described. The TMI moiety is known to be the DNA-binding part of the highly potent anticancer agent duocarmycin A. The ortho-carborane derivatives were prepared from amino alkynes which were bound to a protected TMI carboxylic acid. Addition of decaborane(14) to the alkyne triple bond with subsequent removal of the tert-butoxycarbonyl (Boc) and benzyl protecting groups gave the desired product. Boron uptake from the ortho-carborane derivatives into B-16 melanoma cells was higher and faster than that observed with L-p-boronophenylalanine (BPA), which is in use in the clinic.