Safranine
The safranines are a group of indamine - dyes . They are derivatives of phenazine .
Representative
Their basic structure, the 3,7-diamino-5-phenyl-phenazinium chloride, is called phenosafranine.
Further representatives are u. a. Rhodulinrot G , Rhodulinviolett and safranin . The structurally closely related mauveins are also among the saffronines.
| Safranine | ||||
| Surname | Phenosafranine | Safranin T | Rhodulin red G | Rhodulin violet |
| Basic structure |
 Representation of one of the mesomeric boundary structures |
|||
| R 1 | -H | -CH 3 | -CH 3 | -H |
| R 2 | -NH 2 | -NH 2 | –NHCH 3 | -N (CH 3 ) 2 |
| R 3 | -H | -CH 3 | -CH 3 | -CH 3 |
| CAS number | 81-93-6 | 477-73-6 | 10130-52-6 | 16508-73-9 |
| PubChem | 65732 | 2723800 | 167545 | |
| Molecular formula | C 18 H 15 ClN | C 20 H 19 ClN 4 | C 21 H 21 ClN 4 | C 21 H 21 ClN 4 |
| Molar mass | 322.80 g mol −1 | 350.85 g mol −1 | 364.87 g mol −1 | 364.87 g mol −1 |
The actual dye in saffron , crocetin (8,8′-diapocarotene-8,8′-diacid), on the other hand, has an open-chain polyene structure.
properties
Depending on the structure , the safranines fluoresce from the red to the violet spectral range.
The color of these pigments is due to the large number of resonance structures that are involved in the mesomeric hybrid of their molecules.
use
Safranin was used in leather and paper dyeing, microscopy and as a redox indicator . Today, however, they no longer play a role.
literature
- Safranine . In: Meyers Konversations-Lexikon , 1905.
Individual evidence
- ↑ a b Entry on Safranine. In: Römpp Online . Georg Thieme Verlag, accessed on January 18, 2014.
- ^ Albert Gossauer: Structure and reactivity of biomolecules , Verlag Helvetica Chimica Acta, Zurich, 2006, p. 259, ISBN 978-3-906390-29-1 .