52144-91-9Relevant academic research and scientific papers
A facile preparation of α-aryl carboxylic acid via one-flow arndt-eistert synthesis
Fuse, Shinichiro,Otake, Yuma,Mifune, Yuto,Tanaka, Hiroshi
, p. 1657 - 1661 (2015/11/10)
An efficient, one-flow Arndt-Eistert synthesis was demonstrated. A sequence of acid chloride formation-nucleophilic acyl substitution-Wolff rearrangement-nucleophilic addition was performed in a microflow system without isolating any intermediates, which
Solid-phase synthesis using (Allyloxy)carbonyl(Alloc) chemistry of a putative heptapeptide intermediate in vancomycin biosynthesis containing m-chloro-3-hydroxytyrosine
Freund, Ernst,Vitali, Francesca,Linden, Anthony,Robinson, John A.
, p. 2572 - 2579 (2007/10/03)
A convenient method for the solid-phase synthesis of putative linear heptapeptide intermediates in vancomycin biosynthesis is described, in particular, the heptapeptide D-Leu-Cyt-L-Asn-Hpg-Hpg-Cyt'-Dhpg (Cyt = (2R,3R)-m-chloro-3-hydroxytyrosine, Hpg = (R)-2-(p-hydroxyphenyl)glycine, Cyt' = (2S,3R)-m-chloro-3-hydroxytyrosine and Dhpg = (S)-2-(3,5-dihydroxyphenyl)glycine). The synthesis was performed on chlorotrityl resin and employed the (allyloxy)carbonyl protecting group for temporary N(α) protection during peptide-chain assembly.
A urinary metabolite of Δ1-tetrahydrocannabinol. The first synthesis of 4''-hydroxy-Δ1-tetrahydrocannabinol-7-oic acid labelled with deuterium
Szirmai,Odqvist,Halldin
, p. 309 - 324 (2007/10/03)
The first synthesis of 4''-hydroxy-Δ1-THC-7-oic acid, one of the three major metabolites of Δ1-THC identified in human urine is discussed. Methyl 4-(3,5-dihydroxyphenyl)butanoate (8) was prepared from 3,5-dihydroxybenzoic acid in an overall yield of 15%. 8 was condensed with a terpene synthon (9) under acidic conditions followed by hydrolysis and conversion of the 4''-carboxylic acid function to the corresponding methyl ketone using methyllithium. Reduction with NaBH4 afforded the secondary alcohol in the side-chain. Acetylation and removal of the 1,3-dithiane masking group gave the aldehyde in C-7-position which was further oxidized using NaClO2 followed by deacetylation to give the desired metabolite 14. The same procedure may be used for the synthesis of unlabelled 4''-hydroxy-Δ1-THC-7-oic acid.
Synthesis of Bikaverin
Katagiri, Nobuya,Nakano, Jun,Kato, Tetsuzo
, p. 2710 - 2716 (2007/10/02)
The total synthesis of bikaverin (1b) is described, from everninic acid (5) and 3,5-dihydrobenzoic acid (6).Dieckmann condensation of methyl 2-acetyl-3,5-bis(benzyloxy)phenylacetate (14), synthesised from (6), followed by treatment with protected everninic acid chloride (9) gave 1,3-bisbenzyloxy-6,8-bis(2-benzyloxy-4-methoxy-6-methylbenzyloxy)naphthalene (16).Photoinduced Fries rearrangement of (16) afforded 1,3-bis(benzyloxy)-7-(2-benzyloxy-4-methoxy-6-methylbenzoyl)-6-(2-benzyloxy-4-methoxy-6-methylbenzoyloxy)-8-hydroxynaphthalene (23).Ring closure of (23) with tetramethylammonium hydroxide in pyridine gave the angular benzoxanthene, 1,3-bis(benzyloxy-6-hydroxy)-10-methoxy-8-methylbenzoxanthen-7-one (25), which was oxidized with potassium dichromate to give the orthoquinone, 1,3-bis(benzyloxy)-10-methoxy-8-methylbenzoxanthen-5,6,7-trione (28).By a novel type of rearrangement, (28) was transformed into the linear benzoxanthen, 8,10-bis(benzyloxy)-3-methoxy-1-methylbenzoxanthen-6,11,12-trione (29) by treatment with silica gel.Oxidation and debenzylation of (29) with manganese dioxide in concentrated H2SO4 gave norbikaverin (1a).
Orally active bronchospasmolytic compounds and their preparation
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, (2008/06/13)
Novel compounds are disclosed having useful activity as bronchodilators of improved longevity of action and reduced incidence of side effects. These compounds are described by the formula: EQU1 wherein R1 is a member of the class consisting of tertiary butyl and cyclobutyl, and R2 is a hydrogen or 2 to 5 carbon atom acyl radical, and pharmaceutically acceptable salts thereof. The activity of these compounds is compared to previously known bronchodilators such as 1-(3', 5'-dihydroxyphenyl)-2-(isopropylamino)-ethanol, having the common name orciprenaline, and 1-(3', 4'-dihydroxyphenyl-2-isoproplyamino-ethanol, having the common name isoprenaline.
