Boville, Christina E.; Romney, David K.; Almhjell, Patrick J.; Sieben, Michaela; Arnold, Frances H. published an article in Journal of Organic Chemistry. The title of the article was 《Improved Synthesis of 4-Cyanotryptophan and Other Tryptophan Analogues in Aqueous Solvent Using Variants of TrpB from Thermotoga maritima》.Category: indole-building-block The author mentioned the following in the article:
The use of enzymes has become increasingly widespread in synthesis as chemists strive to reduce their reliance on organic solvents in favor of more environmentally benign aqueous media. With this in mind, we previously endeavored to engineer the tryptophan synthase β-subunit (TrpB) for production of noncanonical amino acids that had previously been synthesized through multi-step routes involving water-sensitive reagents. This enzymic platform proved effective for the synthesis of analogs of the amino acid tryptophan (Trp), which are frequently used in pharmaceutical synthesis as well as chem. biol. However, certain valuable compounds, such as the blue fluorescent amino acid 4-cyanotryptophan (4-CN-Trp), could only be made in low yield, even at elevated temperature (75 °C). Here, we describe the engineering of TrpB from Thermotoga maritima that improved synthesis of 4-CN-Trp from 24% to 78% yield. Remarkably, although the final enzyme maintains high thermostability (T50 = 93 °C), its temperature profile is shifted, such that high reactivity is observed at ∼37 °C (76% yield), creating the possibility for in vivo 4-CN-Trp production The improvements are not specific to 4-CN-Trp; a boost in activity at lower temperature is also demonstrated for other Trp analogs. In addition to this study using 5-Bromo-7-fluoro-1H-indole, there are many other studies that have used 5-Bromo-7-fluoro-1H-indole(cas: 883500-73-0Category: indole-building-block) was used in this study.
5-Bromo-7-fluoro-1H-indole(cas: 883500-73-0) is a member of aromaticfluorinated building blocks. Depending on which substituents are present, fluoroaromatic intermediates can be converted into fluorinated or fluorine-free commercial end products.Fluorine-containing aromatics have been incorporated into drugs (hypnotics, tranquilizers, antiinflammatory agents, analgesics, antibacterials).Category: indole-building-block
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