Question

A peroxo- ligand in this coordination complex is degraded to a single redox-active oxygen atom in “compound I” (“compound one”), which goes on to hydroxylate C-H bonds. Unlike typical square planar complexes, this complex’s d-z-squared orbital lies above the d-sub-xy orbital in energy due to repulsion from a proximal histidine. This complex’s transition from a high-spin domed configuration to a low-spin planar configuration corresponds to a larger system’s T state and (*) R state. (10[1])This cofactor for cytochrome P450s is metabolized to a “verdo-“ form before being cleaved to form biliverdin and then excreted as bilirubin. Due to pi backbonding, this complex undesirably binds very strongly to CO. (-5[1])For 10 points, name this iron-porphyrin complex, four of which appear in a namesake protein that binds molecular oxygen in red blood cells. ■END■ (10[1])

ANSWER: heme [or haem; accept oxo-heme; accept heme B; prompt on hemoglobin or oxohemoglobin or carboxyhemoglobin by asking “what coordination complex is a part of hemoglobin?”]
<JZ, Chemistry>
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Buzzes

PlayerTeamOpponentBuzz PositionValue
Shahar SchwartzBerkeley PastBerkeley B7010
Michal GerasimiukStanfordBerkeley A104-5
Swapnil GargBerkeley AStanford12810

Summary

2024 ARCADIA at UC Berkeley2024-12-06Y2100%0%50%99.00
2024 ARCADIA at GT2024-12-06Y425%0%75%128.00
2024 ARCADIA at Warwick2024-12-06Y5100%0%20%107.60