Table 1. Hydrogen bonding and hydrophobic interactions ofthefour palladaheterocycle enantiomers IIa,a′,b,b′with cytochromes P450 2E1 and P450 2C9 .

Diastereomers	Cytochrome P450 2E1
	E bind , kJ/mol	Hydrogen bonding interaction	Non bonded interaction
IIa	Sterically not complementary
IIb	-37 ± 3.0	‒	Phe106,Ile 115, Phe 116, Phe 203, Asn 204, Asn 206, Phe207, Leu 210, Val 239, Phe298, Ala 299, Clu 302, Thr 303, Leu 363, Val 364, Cys 437, Leu 368, Phe478, Hem 500
IIb′	-26 ± 2.5
IIa′	-31 ± 3.0
Diastereomers	Cytochrome P450 2C9
	E bind , kJ/mol	Hydrogen bonding interaction	Non bonded interaction
IIa	-38 ± 3.0	Phe 476, HOH 602, HOH 701	Phe 100π- π, Leu 102, Ala 103, Phe 114, Ile 205, Leu 208, Ser 209, Ile 213, Asn 217, Leu362, Ser 365, Leu 366, Pro367, Gly 475, Ala 477
IIb	-42 ± 3.0
IIb′	-42 ± 3.5
IIa′	-35 ± 3.0

Amino acid residues of the proteins involved in hydrophobic interactions with ligand molecules are shown in bold.