Tag: M.W=300-350

Girvin, Zebediah C. published the artcileFoldamer-templated catalysis of macrocycle formation, Formula: C13H18BBrO3, the publication is Science (Washington, DC, United States) (2019), 366(6472), 1528-1531, database is CAplus and MEDLINE.

Macrocycles, compounds containing a ring of 12 or more atoms, find use in medicine, fragrances, and biol. ion sensing. The efficient preparation of macrocycles is a fundamental challenge in synthetic organic chem. because the high entropic cost of large-ring closure allows undesired intermol. reactions to compete. Here, we present a bioinspired strategy for macrocycle formation through carbon-carbon bond formation. The process relies on a catalytic oligomer containing α- and γ-amino acid residues to template the ring-closing process. The α/γ-peptide foldamer adopts a helical conformation that displays a catalytic primary amine-secondary amine diad in a specific three-dimensional arrangement. This catalyst promotes aldol reactions that form rings containing 14 to 22 atoms. Utility is demonstrated in the synthesis of the natural product robustol.

Science (Washington, DC, United States) published new progress about 401797-04-4. 401797-04-4 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronate Esters,Boronic acid and ester, name is 2-(3-Bromo-5-methoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, and the molecular formula is C13H18BBrO3, Formula: C13H18BBrO3.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Abadleh, Mohammed M. published the artcileThiophene ring-opening reactions. Direct access to the synthesis of 1,3,4-thiadiazoline-(condenced) pyridone hybrids, SDS of cas: 52431-30-8, the publication is Tetrahedron (2021), 131957, database is CAplus.

The reaction of N’-(aryl)benzothiohydrazides with 2-chloro-7-cyclopropyl-3-nitro-4-oxothieno[2,3-b]pyridine-5-carboxylic ester/acid in the presence of triethylamine furnished, upon addition of iodomethane, the resp. 1,3,4-thiadiazoline-(6-methylthio-4-oxopyridine) hybrids. Interestingly, the reaction of thiohydrazides with 4-oxothieno[2,3-b]pyridines incorporating N1-(2′-halogeno-5′-nitrophenyl) entities generated 1,3-thiazoline ring embedded in the resulting [fused]-tricyclic products. Similarly, the N1-(2′-chloropyridin-3′-yl) analog produced the resp. thiazolo[3,2-a: 5,6-b’]dipyridine-thiadiazoline hybrid. Monocyclic 2-chloro-3-nitrothiophenes in their reaction with benzothiohydrazide formed notable thiophene ring-opening products. This behavior is verified by quantum mech. calculations A proposed mechanistic pathway for this new reaction involving preferential predominance of thiophene ring-opening over Smiles rearrangement is presented.

Tetrahedron published new progress about 52431-30-8. 52431-30-8 belongs to bromides-buliding-blocks, auxiliary class Liquid Crystal &OLED Materials, name is 2,5-Dibromo-3,4-dinitrothiophene, and the molecular formula is C4Br2N2O4S, SDS of cas: 52431-30-8.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary

Hagiwara, Keita published the artcileAn aqueous molecular tube with polyaromatic frameworks capable of binding fluorescent dyes, Category: bromides-buliding-blocks, the publication is Chemical Science (2015), 6(1), 259-263, database is CAplus and MEDLINE.

An aqueous mol. tube composed of polyaromatic frameworks with peripheral hydrophilic groups was prepared The new tube had a well-defined hydrophobic cavity with a diameter of 1̃ nm and quant. could bind two mols. of fluorescent coumarin dyes in aqueous solutions The bound coumarin dimers in a stacked fashion exhibited unusual excimer-like emissions in the confined space through efficient host-guest energy transfer.

Chemical Science published new progress about 401797-04-4. 401797-04-4 belongs to bromides-buliding-blocks, auxiliary class Bromide,Boronic acid and ester,Benzene,Ether,Boronate Esters,Boronic acid and ester, name is 2-(3-Bromo-5-methoxyphenyl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, and the molecular formula is C13H18BBrO3, Category: bromides-buliding-blocks.

Referemce:
https://en.wikipedia.org/wiki/Bromide,
bromide – Wiktionary