Ligands boron-containing

Bergseid et al. (2000) also reported on the use of SHA-activated chromatography supports for the coupling of boronate-containing affinity ligands. In this case, immobilized RNase A was used to purify anti-RNase antibodies from antiserum samples. RNase A was modified with an NHS-PDBA crosslinker at a molar ratio of 100 1 (crosslinkenprotein), purified to remove excess crosslinker, and then coupled to an SHA-agarose support in 0.1 M sodium bicarbonate, pH 8.0. 

Even before the discovery of the katapinands vide supra), work upon bidentate Lewis acid hosts suggested the possibility of chelation of anionic sjjecies by acyclic-boron-containing ligands such as BF2CH2CH2BF2. In many ways mul-... 

Heterocyclic ring complexes, and boron-containing rings, 3,42 Hetero-[4+3]-cycloadditions, characteristics, 10, 617 j5-Heterocyclopentadienyl complexes, with platinum, rf-boron-carbon ligands, 8, 663... 

At present, boron-containing compounds and their metal complexes are of considerable interest. Amongst them are found the coordination compounds 545-547 of transition metals containing boryle and borylene ligands [942] ... 

The heterocyclic compounds occupy an important place amongst boron-containing ligands [8], It is well known that borazines, having a six-member ring, form ri6(7i)-complexes, for example 554 [953], It was recently shown that cr(B)-metal-coordinated compounds of type 555 may also be obtained on the basis of this ligand system [954a] ... 

On the basis of similar five-member cycles were obtained the r 5(7i)-complex compounds of type 556 [7, vol.3 8]. In this respect, we note that the r "(7i)-metal-binding shown by 557-560 is formed in complexes of five- and six-member boron-containing carbocyclic ligands (n = 5 and 6, respectively) [8,942,954b]. A variety of similar structures are presented in Ref. 184f. 

In the introductory section, a short historical outlook is presented to introduce the few 99mTc radiopharmaceuticals based on phosphorus- and boron-containing ligands already in clinical use. Generic considerations of the characteristics of these ligands are included in this... 

Other boron-containing ligands hke 1,2- and 1,3-thiaborollides or 1,2-benzothiaborollide can also give rise to various metallocenes (61, 62) analogons to cyclopentadienyl or indenyl ones. 

Interestingly, the difference in ligand orientation between Bpin and Beat systems is found to be mainly steric in origin. In the case of Bpin system 9.10 the perpendicular orientation allows for interaction of boryl and hydride ligands via the formally vacant BO2 7t orbital (to which the B 2pz orbital is a major contributor) in a manner reminiscent of conventional boron-containing Lewis acids. In the case of Beat system 9.9, however, the near coplanar arrangement of ClRhB and BO2 planes means that the B- -H interaction involves the perpendicular BO2 a as the acceptor orbital (Fig. 29) [154]. 

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