New Unnatural Boron-Containing Amino Acids and Peptides as Potential Delivery Agents for Neutron Capture Therapy
Since Boron Neutron Capture Therapy is to be used in the treatment of primary and metastatic brain tumors, it is essential that the boron compounds be capable of crossing the blood-brain barrier (BBB) prior to their incorporation into tumor cells. It has been shown1 that derivatives of L-phenylalanine are transported across the BBB by neutral amino acid transport system. Recently, a method has been developed to deliver low molecular weight peptides into brain.2 These observations suggest that boronated analogues of phenylalanine itself and their peptides modified by replacing aromatic amino acids with highly lipophilic, carborane-containing amino acids might be used to reach and become incorporated into brain tumor cells protected by BBB.
KeywordsAromatic Amino Acid Boron Neutron Capture Therapy Metastatic Brain Tumor Benzyl Ester Brain Tumor Cell
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