Photochemistry of MTM- and MTE-esters of ω-phthalimido carboxylic acids: Macrocyclization versus deprotection was written by Griesbeck, Axel G.;Oelgemoller, Michael;Lex, Johann. And the article was included in Journal of Organic Chemistry in 2000.Computed Properties of C12H11NO4 This article mentions the following:
The photolysis of linear methylthiomethyl (MTM) esters of ω-phthalimido carboxylic acids, Pht-(CH2)n-CO2CH2SCH3 (I; Pht = phthalimido; n = 1, 2, 3, 5, 10), of methylthioethyl (MTE) esters Pht-(CH2)n-CO2CH2CH2SCH3 (II; Pht = phthalimido; n = 1, 3), and of two methyl-substituted esters Pht-CHMeCH2CO2CH2SMe (III) and (S)-Pht-CHMeCO2CH2CH2SMe (IV) resulted in photocyclization to give medium-sized and macrocyclic rings and in photochem. deprotection to give the free carboxylic acids. Photocyclization of I (n = 2, 3) gave the macrocyclic lactones V (n = 2, 3) in excellent yields whereas the substrates I (n = 1, 5, 10) with shorter as well as longer spacer groups gave preferentially deprotected carboxylic acid products. Subsequent photolysis of I (n = 1) gave N-methylphthalimide. Photolysis of the MTE esters II gave the macrocyclic lactones VI and VII. Thus, competition between cyclization and deprotection strongly depended on the chain length of the hydrocarbon linker between phthalimido chromophore and ester group. To examine the influence of the position of the ester group in the linker chain the model substrates III and IV with identical number of atoms separating electron donor and acceptor group were investigated. The more flexible MTE derivative IV cyclized to give a 4:1 diastereoisomeric mixture of 11(S)-cis/trans-indenooxathiaazacyclononanones VIII, whereas photolysis of the more reluctant MTM ester III gave cis-indenooxathiaazacyclononanone IX only after prolonged irradiation Thus, the methylthiomethyl group can function as a photolabile protecting group whereas the methylthioethyl group cannot be removed photochem. The distance dependence of the secondary reaction steps indicates that the primary electron transfer is not necessarily induced starting from close contact geometries. In the experiment, the researchers used many compounds, for example, 4-(1,3-Dioxoisoindolin-2-yl)butanoic acid (cas: 3130-75-4Computed Properties of C12H11NO4).
4-(1,3-Dioxoisoindolin-2-yl)butanoic acid (cas: 3130-75-4) belongs to indole derivatives. In addition to tryptophan, indigo, and indoleacetic acid, numerous compounds obtainable from plant or animal sources contain the indole molecular structure. They are capable of binding to a variety of receptors with high affinity and thus have applications in a wide range of therapeutic areas.Computed Properties of C12H11NO4
Referemce:
Indole alkaloid derivatives as building blocks of natural products from Bacillus thuringiensis and Bacillus velezensis and their antibacterial and antifungal activity study,
Preparation of Indole Containing Building Blocks for the Regiospecific Construction of Indole Appended Pyrazoles and Pyrroles