240
R. Barbieri et al.
Table 12.5. Molecular dynamics data for representative complexes of Me2Sn(IV) and MeSn(IV) with
2-mercaptopyrimidine (HSPym)a and 2-mercaptopyridine (HSPy)a, respectively, interacted with DNA,
as determined by variable temperature 119Sn Mossbauer spectroscopy
No. b System
C
10 2 dln(A r l A n3 ) I dt Trange
References
(K-')
(K)
2
Me 2 Sn(SPym)(DNA monomer)
Barbieri et al. 1999
gel
- 1.228 (O.989)
77.3-140.5
lyophil.
- 1.309 (O.996)
77.3-240.75
5
MeSn(SPY}2(DNA monomer}
Rossi 1994; Barone 1997
gel
- 1.364 (0.983)
77.3-181.9
lyophil.
-0.639 (O.980)
77.3-207.5
lyophil.
- 1.420 (O.982)
210.0-290.0
~ See Fig. 12.2.
Correspond to No.s in Table 12.4.
C Composition is attributed on the basis of the value r = [Sn] / [DNA monomer] employed in the
condensation process (see note b in Table 1 2.4) as well as of the composition of RnSn-DNA
condensates reported in Table 12.3. See also note a in Table 12.3.
d Slopes of normalized total areas under the resonant peaks vs. T; correlation coefficients in
parentheses.
Table 12.6. 119Sn Mossbauer parameters for 111 systems Alk2SnCl2/L-cysteine and Alk2SnC12/3mercaptopropionic acid, interacted with DNA (111), and Et2SnCI2 interacted with DNA-L-cysteine
[1/(111»)
No. System
a
Absorber sample
t
flE>
r"r2 b • C Reference
(mms-') (mms-') (mms-')
[(Me 2 SnCI 2 }(HS-COOH}]d
Solutions in Hp
1.24-1.34 2.98-3.23 0.81
Barbieri 1995
+DNA
pH = 4.80-5.94
2 (Me 2 SnCl)(HS-COOH)
Solutions in Hp
1.26-1.30 2.98-3.26 0.80
pH = 4.33-4.36
3 Et 2 SnCl 2 + [(L -cys)(DNA}]"
Pellet, gel
1.53
4.51
0.79
4
id.
Supematant f
1.47
3.67
0.98
pH=3.23
5 Et 2 SnCl 2 + (L _cys}e
Solutions in Hpf
1.45
3.26
0.75
pH =3.42
a HS-COOH stands for both 3-mercaptopropionic acid, HSCH 2 CH COOH, and L-cysteine,
HSCH 2 CH(NH 2 }COOH. Molar ratios are generally 1 /1, DNA stan~ing for DNA monomer (MW = 315,
calf thymus DNA). Aqueous solutions are employed, unless otherwise stated; DNA was buffered with
Tris-EDTA.
b See note b to Table 12.2. Limiting data for series of spectra are reported, measured at 77.3 K.
C Average values.
d Includes a solution of Me 2 Sn[SCH 2 CH(NH 2 }COO] in Hp.
; Ethanol solutions of Et 2 SnCI 2 are employed.
Ethanol S; 10% vol.
R. Barbieri et al.
Table 12.5. Molecular dynamics data for representative complexes of Me2Sn(IV) and MeSn(IV) with
2-mercaptopyrimidine (HSPym)a and 2-mercaptopyridine (HSPy)a, respectively, interacted with DNA,
as determined by variable temperature 119Sn Mossbauer spectroscopy
No. b System
C
10 2 dln(A r l A n3 ) I dt Trange
References
(K-')
(K)
2
Me 2 Sn(SPym)(DNA monomer)
Barbieri et al. 1999
gel
- 1.228 (O.989)
77.3-140.5
lyophil.
- 1.309 (O.996)
77.3-240.75
5
MeSn(SPY}2(DNA monomer}
Rossi 1994; Barone 1997
gel
- 1.364 (0.983)
77.3-181.9
lyophil.
-0.639 (O.980)
77.3-207.5
lyophil.
- 1.420 (O.982)
210.0-290.0
~ See Fig. 12.2.
Correspond to No.s in Table 12.4.
C Composition is attributed on the basis of the value r = [Sn] / [DNA monomer] employed in the
condensation process (see note b in Table 1 2.4) as well as of the composition of RnSn-DNA
condensates reported in Table 12.3. See also note a in Table 12.3.
d Slopes of normalized total areas under the resonant peaks vs. T; correlation coefficients in
parentheses.
Table 12.6. 119Sn Mossbauer parameters for 111 systems Alk2SnCl2/L-cysteine and Alk2SnC12/3mercaptopropionic acid, interacted with DNA (111), and Et2SnCI2 interacted with DNA-L-cysteine
[1/(111»)
No. System
a
Absorber sample
t
flE>
r"r2 b • C Reference
(mms-') (mms-') (mms-')
[(Me 2 SnCI 2 }(HS-COOH}]d
Solutions in Hp
1.24-1.34 2.98-3.23 0.81
Barbieri 1995
+DNA
pH = 4.80-5.94
2 (Me 2 SnCl)(HS-COOH)
Solutions in Hp
1.26-1.30 2.98-3.26 0.80
pH = 4.33-4.36
3 Et 2 SnCl 2 + [(L -cys)(DNA}]"
Pellet, gel
1.53
4.51
0.79
4
id.
Supematant f
1.47
3.67
0.98
pH=3.23
5 Et 2 SnCl 2 + (L _cys}e
Solutions in Hpf
1.45
3.26
0.75
pH =3.42
a HS-COOH stands for both 3-mercaptopropionic acid, HSCH 2 CH COOH, and L-cysteine,
HSCH 2 CH(NH 2 }COOH. Molar ratios are generally 1 /1, DNA stan~ing for DNA monomer (MW = 315,
calf thymus DNA). Aqueous solutions are employed, unless otherwise stated; DNA was buffered with
Tris-EDTA.
b See note b to Table 12.2. Limiting data for series of spectra are reported, measured at 77.3 K.
C Average values.
d Includes a solution of Me 2 Sn[SCH 2 CH(NH 2 }COO] in Hp.
; Ethanol solutions of Et 2 SnCI 2 are employed.
Ethanol S; 10% vol.