A pair of enantiomerically pure metallodimers containing two deeply concave tribenzotriquinacene (TBTQ) units linked by a platinum-diacetylene unit were synthesized. Such linear metal-centered TBTQ dimers are considered as edges of metallosquares and metallocubes that bear four or eight mutually syn-oriented TBTQ bowls at their tips, respectively. The structures of the metallodimers were characterized by 1H, 13C and 31P NMR spectroscopy, ESI mass spectrometry, and circular dichroism. The single X-ray crystal structure of (+)-enantiomer confirmed the absolute configuration of the metallodimers and revealed an edge (tip-to-tip) length of 18.456 Å and an approximated syn-orientation of the two TBTQ bowls in the solid state.
Structural characterization of lipoarabinomannans from Mycobacterium tuberculosis and Mycobacterium smegmatis by ESI mass spectrometry