Table 1.
13C isotropic chemical shifts for components common to insect cuticle. The original values for cuticle components from the Schaefer et al. paper appear in the table [7]. A similar table was published by Peter et al. [6]. The repeat unit for chitin, along with carbon position labels, is shown for reference.
| 13C resonance position (ppm) | Assignment |
|---|---|
| 172 | Carbonyl carbons of chitin, protein, lipid, and catechol acyl groups |
| 170 | Carbonyl carbons of oxalate |
| 155 | Phenoxy carbon of tyrosine, guanidino carbons in arginine |
| 144 | Phenoxy carbons of catechols |
| 129 | Aromatic carbons |
| 116 | Tyrosine carbons 3 and 5, imidazole carbon 4, catechol carbons 2 and 5 |
| 104 | Chitin carbon 1 |
| 82 | Chitin carbon 4 |
| 75 | Chitin carbon 5 |
| 72 | Chitin carbon 3 |
| 60 | Chitin carbon 6, amino acid α-carbons |
| 55 | Chitin carbon 2, amino acid α-carbons |
| 44 | Aliphatic carbons of amino acids, catechols, and lipids |
| 33 | Aliphatic carbons of amino acids, catechols, and lipids |
| 30 | Aliphatic carbons of lipids |
| 23 | Methyl carbons of chitin, protein, lipid, and catechol acyl groups; amino acid methyne carbons |
| 19 | Methyl carbons of amino acids and lipids |
