2- Aminoindane-2-phosphonic acid

Taking into account the essential role of PAL activity in the appearance of RS, Peiser et al. [146] studied whether the application of various inhibitors of PAL activity could prevent the development of RS lesions in lettuce midribs. The use of the inhibitor 2-aminoindan-2-phosphonic acid (AIP) sharply diminished the formation of phenolic compounds, although this did not reduce the number of lesions associated with RS [146]. In short, according to the results of Peiser et al. [146], the early development of RS lesions is independent of the increase in PAL activity and phenolic compounds, rather than resulting from these increases as previously suggested. However, the accumulation of phenolic compounds does contribute to the subsequent browning symptoms indicative of RS. 

C Appert, J Zoh, N Amrhein (2003) Kinetic analysis of the inhibition of phenylalanine ammonia-lyase by 2-aminoindan-2-phosphonic acid and other phenylalanine analogues Phytochemistry 62(3) 415-422... 

J Zoh, P Miziak, N Amrhein, R Gancarz (2005) Inhibitors of Phenylanine Ammonia-Lyase (PAL) Synthesis and Biological Evaluation of 5-Substituted 2-Aminoindane-2-phosphonic Acids Chemistry and Biodiversity 2(9) 1187—1194... 

Zont, J. and Amrhein, N. (1992) Inhibitors of phenylalanine ammonia-lyase 2-aminoindan-2-phosphonic acid and related compormds. Liebigs Ann. Chem., 625-8. 

The importance of SA in the activation of resistance was further underscored by the demonstration that otherwise resistant Arabidopsis plants become susceptible to Peronospora parasitica when phenylalanine ammonia lyase (PAL) activity is specifically inhibited by 2-aminoindan-2-phosphonic acid [77]. Since PAL catalyzes the first step in the SA biosynthetic pathway and resistance was restored in these PAL-suppressed plants by exogenous application of SA, increased susceptibility is presumably caused by a block in SA synthesis. Likewise, tobacco plants exhibiting epigenetic suppression of PAL gene expression due to cosuppression do not develop SAR in response to TMV infection [78]. In addition, these plants fail to systemically express the PR-la gene after TMV infection. 

Antagonists of metabotropic glutamate receptors and G-protein-coupled receptors associated with various neurodegenerate diseases have been prepared by proline-catalyzed direct a-amination reactions (Scheme 2.30) [7c]. Both, indane carbaldehyde 10 and analogous compounds having an ester functionality [leading to l-aminoindan-l,5-dicarboxylic acid (AIDA)] and or a phosphonate substituent [(RS)-l-amino-5-phosphonoindan-l-carboxylic acid APICA], all reacted with di-... 

---