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“CTP”
cinnamyltriphenylphosphonium
chloride
Cytotoxin
Molecular Weight: 414.906221 g/mol
Structure: Three benzene rings and
cinnamyl group attached to phosphorous
central atom. Chloride anion.
Physical Properties:
Melting Point: 225 º – 227 º C
Appearance: White to Off-White Powder or
Crystalline Powder
IR Spectrum of CTP
If a  is being absorbed, it means that energy (E = h) is being absorbed by the cmpd.
Energies in the IR region correspond to the energies involved in bond vibrations (stretches/bends).
3100 - 3000 =C-H (aryl) stretch
2000 - 1665 weak overtones of aromatic
1600 - 1585, 1500 -1400 C=C stretch (in ring)
3000 - 2850 C-H (alkyl) stretch
1470 - 1450 C-H (alkyl) bend
1000 - 650 =C-H (alkene) bend
DNA Melting Curve
dsDNA
2 ssDNA
Tm = Melting Point of DNA
Half of DNA has uncoiled and
remains single-stranded when
the melting temperature is
reached
A shift in Melting Temperature is a strong indicator of the
presence of an interaction between the DNA and any small
molecule, such as any arylphosphonium salt.
Sample
Melting
Temp. (ºC)
Native
Salmon DNA + 3µL
Salmon DNA + 5µL
Salmon DNA (15.2µg/150µL DMSO) (15.2µg/150µL DMSO)
CTP
CTP
64.6
67.2
67.8
DNA/CTP Melting Curve Experiment Summary
120
100
D Absorbance
80
60
40
Native Salmon DNA
20
Salmon DNA + TCP (3 microliters)
Salmon DNA + TCP (5 microliters)
0
40
50
60
70
-20
Temperature (degrees Celsius)
80
90
100
DNA/CTP Melting Point Experiment Summary - Derivative Plots
0.09
0.08
0.07
delta A/delta T
0.06
0.05
0.04
Native Salmon DNA
Salmon DNA + TCP (3 microliters)
Salmon DNA + TCP (5 microliters)
0.03
0.02
0.01
0
40
50
60
70
80
-0.01
Average Temperature (degrees Celsius)
90
100
Gel Electrophoresis
Lane 2: (Control)
Digested DNA
Lane 3: (Experimental)
Digested DNA w/ 1ml CTP
Gel Electrophoresis: Digested Plasmid DNA
Movement and Determination of Base Pairs
10000
# of Base Pairs
~ 5000 base pairs
(qualitative trial)
1000
20
25
30
35
40
45
50
55
Distance from Well (mm)
60
65
70
HyperChem Predictions
• CTP would bind effectively with the DNA
through intercalation. This was based
upon the flat, characteristic structure of
the cinnamyl group.
• CTP might also bind with DNA in its major
groove, based on the relative size of the
benzene groups and the electrostatic
attraction of the phosphorous backbone
of DNA.
HyperChem Computations
Minor groove interactions were most
favorable with cinnamyl group in closest
proximity to DNA:
Distance of two closest atoms = 3.8913 Å
E = 14.699580 kcal
Gd = 0.099771
HyperChem Predictions
HyperChem Computations
Intercalation and Major Groove Interactions
of CTP and DNA were of greater energy:
Major Groove Triphenyl group of closest proximity to DNA
E = 894.84832 kcal
Cinnamyl group
E = 898.00171 kcal
Intercalation – (Interaction optimized with CTP passing through
nitrogen base of cytosine)
Triphenyl group of closest proximity to DNA
E = 1553.85107 kcal
Cinnamyl group through base pairs in major groove
E = 923.01587 kcal
Further Research
• Nature of DNA Cooling after denaturation
and possible restructuring of DNA
• DNA Structure effects on Movement
through gel
• Potential Applications of the CTP Molecule
in DNA of organisms
• Further HyperChem Computations
• Ultimate objective: X-ray crystallography
(orientation and type of interaction)