PMC

(A) di-halogenated bent metallocenes; (B) 1,1′-halometallocenes (the numbering is the one used in this text. Hydrogen atoms get their numbering from the respective carbon atoms. In the text and Tables ring C1–C5 will be mentioned as ring I, while ring C6–C10 will be ring II).

a The X-ray crystal structure of CPOC-301. b The solid-state molecular packing of CPOC-301 viewed from [001] direction, where H atoms are omitted for clarity. color codes: phenyl ring; orange, carbon; gray, oxygen; red, nitrogen; blue, and hydrogen; light turquoise.

Examples of an aromatic residue (shown in magenta) interacting with the sterol ring of cholesterol. A) Phe33 interacts the α face of the sterol ring in a Na⁺, K⁺-ATPase (PDBID: 4HYT, cholesterol 1 ). B) Trp981 interacts the β-face of cholesterol in a Na⁺, K⁺-ATPase (PDBID: 4HYT, cholesterol 2 ). C) Phe255 interacts the α face of the sterol ring in the adenosine receptor A2α (PDB ID: 4EIY). D) Trp158 interacts the α-face of cholesterol in the β2-adrenergic receptor (PDB ID: 2RH1). All carbon atoms in cholesterol and aromatic residues are displayed with spheres with a radius of 1.7 Å. E) Cholesterol sandwich packing configuration with Phe255 in the middle and cholesterols on each side in the adenosine receptor A2α (PDBID: 4EIY). The C5=C6 double bonds (shown in orange) are parallel to the face of the aromatic ring. F) Aromatic sandwich packing configuration with a cholesterol in the middle and Tyr299 and Phe313 on each side in the μ-type opioid receptor (PDBID: 4DKL). The C5=C6 double bond (shown in orange) is parallel to the faces of the aromatic rings. G) Interaction between the Phe203 ring of the Niemann-Pick C1 protein and the cholesterol double bond (PDBID: 3GKI). H) Interaction of F82 of with the C5=C6 group of CYP11A1 (a cytochrome p450, PDBID: 3N9Y).

Schematic view of the packing method. The general procedure of the random circle packing method, including: (a) initialization; (b) adding the second CNT; (c) locating the sixth CNT; and (d) locating the nineteenth CNT. Each ring represents the cross-section of a CNT. A presentative CNT bundle containing 19 SWNTs: (e) the cross-sectional view, and (f) the side view.