New Di- and Triorganotin(IV) Tyrosylalaninates as Models for Metal—Protein Interactions: Synthesis, Structural Characterization, and Potentiometric Studies of Tyrosylalanine, Glycyltyrosine, and Glycylisoleucine with Di- and Trimethyltin(IV) Moieties in Aqueous Medium

Table 3

¹¹⁹Sn Mössbauer spectral data (80 K) of di- and triorganotin(IV) tyrosylalaninates^a.

Compound no.	QS (mm s^−1)	IS (mm s^−1)	ρ (QS/IS)	𝜏1 (L)	𝜏2 (R)	∠C–Sn–C^b (°)
Me2Sn(Tyr-Ala)	3.28	1.23	2.67	1.09	1.42	135.67
n-Bu2Sn(Tyr-Ala)	2.58	1.11	2.32	1.31	1.59	115.81
n-Oct2Sn(Tyr-Ala)	3.41	1.39	2.45	0.97	1.07	131.62
Ph2Sn(Tyr-Ala)	2.35	0.91	2.58	1.27	2.0	114.85
Me3Sn(HTyr-Ala)	3.32	1.26	2.63	1.0	1.22	136.86
Ph3Sn(HTyr-Ala)	2.13	0.97	2.20	1.08	1.20	107.01

^aQS: quadruple splitting; IS: isomer shift relative to BaSnO₃ and tin foil (splitting: 2.52 mm s⁻¹); 𝜏₁ (L): half line-width left doublet component; 𝜏₂ (R): half line-width right doublet component.
^bParish’s relationship [35]: QS = 4[R][1–(3/4)sin²2θ]^1/2, where ∠C–Sn–C = (180–2θ)° and [R] is the partial quadruple splitting (p.q.s.). For alkyl and phenyl groups, R = −1.03 and −0.95 mms⁻¹, respectively [35, 44].