Table 4. Cross-linking of AG₃(T₂AG₃)₃ I and (T₂AG₃)₄ II by cis- or trans-[Pt(NH₃)₂(H₂O)₂]²⁺ 1 and 2: correlation between the identified platinated purines, their platinum chelation ability and their N–N distances measured on the NMR (A) and X-ray (B) structures of I.

Theoretical cross-links inferred from the identified platinated sites of I and II by 1 and 2		Distances (Å) between the purine nitrogens of the theoretical chelates on structures A and B
		A	B
Top of A
A1–G10	A1N1–G10	4.2–6.9	25.1
1 and 2	A1N7–G10	6.4–6.9	22.2
A13–G22	A13N1–G22	3.5–5.4	21.3
1 and 2	A13N7–G22	3.9–6.2	21.8
A1–A13	A1N1–A13N1	7.8–11.5	33.7
2	A1N1–A13N7	5.1–8.4	34.8
	A1N7–A13N1	6.6–10	31.1
	A1N7–A13N7	3–6.8	32.3
A1–G22a	A1N1–G22	9–12.3	16
	A1N7–G22	8.8–9.6	12.6
Bottom of A
A7–A19	A7N1–A19N1	4.6–4.8	30.8
2	A7N1–A19N7	6.1–6.4	31.4
	A7N7–A19N1	4.7–7.1	31.6
	A7N7–A19N7	6.7–7.8	32.4
G4–A19	G4–A19N1	4.2–5.9	21.9
2	G4–A19N7	6.1–8.1	21.8
A7–G20	A7N1–G20	5.5–5.9	19.7
2	A7N7–G20	8.1–8.6	21.1

^aA1–G22 platinum chelation is not feasible because of the too long N–N distances between the purines. The two purines are involved in other cross-links.