Synthesis of Novel Carborane-hybrids Based on a Triazine Scaffold for Boron Neutron Capture Therapy

Abstract

Cyanuric chloride has been used as a scaffold for the synthesis of potential agents for BNCT containing a carborane cluster, a sugar moiety as hydrophilic arm and an amino acid for the con­jugation with bioactive molecules; this approach is, in principle, particularly suitable for a combinatorial approach.

Key words

carborane cluster - glycosides - amino acids - boron - medicinal chemistry

References

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14

Reaction conditions: Z-α-N-l-lysine, 2 equiv DIPEA, MeCN, 15 min, r.t.; then, 7a or 7b, 48 h, 80 °C.

15

Selected data for final compounds. MALDI-MS: 8a calcd for C₂₇H₄₇B₁₀N₅O₁₂S: 773.9; found: 796.0 [M + Na]⁺, 812.8 [M + K]⁺; 8b calcd for C₃₉H₆₃B₁₀N₅O₂₀S: 1062.1; found: 1085.2 [M + Na]⁺, 1101.2 [M + K]⁺; 9a calcd for C₃₂H₅₆B₁₀N₆O₁₄S: 889.0; found: 928.44 [M + K]⁺; 12b calcd for C₄₄H₇₂B₁₀N₆O₂₂S: 1177.2; found: 1216.3 [M + K]⁺. ¹¹B NMR (CD₃OD): 8a -3.62 (2 B), -10.54 (4 B), -12.36 (4 B); 8b -3.59 (2 B), -10.47 (4 B), -12.22 (4 B); 9a -3.55 (2 B), -10.50 (4 B), -12.25 (4 B); 9b -3.64 (2 B), -10.45 (4 B), -12.18 (4 B).