Introduction
Chemical Properties
Synthesis
Derivatives
How it works
Symptoms
Treatment
Research
Reference
 
Any suggestions or comments, please contact me at
shuyi.quek@ic.ac.uk
 
 
 
 
 

- Chemical Properties -

New Scientist January 20, 2001
" [Tetrodotoxin] is not an alkaloid, steroid or carbohydrate and it is not
like any conventional amino acid. It's a low molecular weight, small molecule
with a unique cage structure. "

-- as described by Harry Mosher (Stanford University) who isolated the
toxin in the 1960s.

Name (IUPAC): Octahydro-12-(hydroxymethyl)-2-imino-5, 9:7, 10a-dimethano-10aH-[1,3]
dioxocino[6,5-d]pyrimidine-4,7,10,11,12-pentol

CAS number: 4368-28-9

Molecular Formula: C11H17N3O8

Molecular Weight: 319.2706

Property
Calculated Value1
Condition
Boiling Point
772.1 70.0XC
Pressure: 760.0 Torr
Enthalpy of Vapourisation
128.15 6.0 kJ/mol
 
Vapour Pressure
1.58E-27 Torr
Temp: 25 XC
Flash Point
420.7 64.2 XC
 
H acceptor
11
 
H donor
9
 
pKa
9.70 0.70
most acidic
pKa
11.94 0.70
most basic
1 Calculated using Advanced Chemistry Development (ACD) software Solaris Version 4.67

-white crystalline solid

- water soluble non-protein

-Heat stable (except in allkaline environment)

-darkens above 220XC without melting

- weak base pKa 8.7

-odourless

Tetrodotoxin exists in an equilibrium mixture of its ortho ester, anhydride and lactone forms


"Equilibrium mixture"
-http://www.scripps.edu/chem/baran/images/grpmtgpdf/Vasan.pdf


"Picture of Tetrodotoxin molecule in mol format"


"Various representations of Tetrodotoxin"
- http://www.life.umd.edu/grad/mlfsc/zctsim/Tetrodo.html

IR, NMR and Mass spectrum can be viewed here

The molecule consists of

- a positively charged Guanidinium group (3 Nitrogen atoms)
The resultant cation is stablised by resonance effect.

Guanidinium group

- Pyrimidine ring fused with other ring systems.
Of the additional ring systems, 5 of the rings contain the -OH group, which increases
the stability and ability of the toxin to bind to the aqueous interfaces in the cell.

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