Cycloadditions of substituted benzopyran-4-ones to electron-rich dienes: a new route to xanthone derivatives

Cremins, Peter J.; Saengchantara, S. T.; Wallace, Timothy W.

doi:10.1016/s0040-4020(01)86849-6

Cited by 61 publications

(13 citation statements)

References 24 publications

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“…In contrast, under the same reaction conditions, compound 5 bearing a naphthalene ring afforded lactone 11a, derived from the 1,4-addition of n-BuLi, in 41% yield, as well as compounds 9a 21) (10%) and 10a 22) (32%). Interestingly, Talinli et al also reported the reaction between compound 5 and n-BuLi in toluene, which afforded compound 10a and its dehydrated derivative in 75 and 5% yields, respectively, 22) representing a quite different product distribution to that observed in the present study. These data suggested that the solvent played an important role.…”

Section: Introductioncontrasting

confidence: 77%

Nucleophilic Addition Reaction with Dearomatization of Naphthalene Ring

Sasaki

Kiyotaki

Imayoshi

et al. 2020

CHEMICAL & PHARMACEUTICAL BULLETIN

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Various aromatic lactones have been synthesized and their regioselectivity (1,2-addition vs. 1,4-or 1,6-addition) investigated in reactions with organolithium species, particularly n-BuLi and sec-BuLi. The regioselectivity varied greatly depending on various factors, such as the bulkiness of both substrates and organolithium species, and types of solvent and cosolvent. In particular, 1,4-addition with dearomatization occurred preferentially using sec-BuLi as the nucleophile in tetrahydrofuran (THF) with hexamethylphosphoramide (HMPA) or N,N′-dimethylpropyleneurea (DMPU) as cosolvent. For sec-BuLi, the reaction was estimated to proceed through a single-electron transfer mechanism.

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Section: Introductioncontrasting

confidence: 77%

Nucleophilic Addition Reaction with Dearomatization of Naphthalene Ring

Sasaki

Kiyotaki

Imayoshi

et al. 2020

CHEMICAL & PHARMACEUTICAL BULLETIN

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“…Although chromones were used previously in Diels-Alder reactions with various dienes, invariably successful Diels-Alder reactions required the presence of electron-withdrawing carbonyl- or cyano- group in position 3 of chromone ring. [10]…”

Section: Resultsmentioning

confidence: 99%

Antineoplastic Isoflavonoids Derived from Intermediate ortho‐Quinone Methides Generated from Mannich Bases

et al. 2016

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The regioselective condensations of various 7-hydroxyisoflavonoids with bis(N,N-dimethylamino)methane in a Mannich reaction provided C-8 N,N-dimethylaminomethyl-substituted isoflavonoids in good yield. Similar condensations of 7-hydroxy-8-methylisoflavonoids led to the C-6 substituted analogs. Thermal eliminations of dimethylamine from these C-6 or C-8 N,N-dimethylaminomethyl-substituted isoflavonoids generated ortho-quinone methide intermediates within isoflavonoid frameworks for the first time. Despite other potential competing outcomes, these ortho-quinone methide intermediates trapped dienophiles including 2,3-dihydrofuran, 3,4-dihydro-2H-pyran, 3-(N,N-dimethylamino)-5,5-dimethyl-2-cyclohexen-1-one, 1-morpholinocyclopentene, and 1-morpholinocyclohexene to give various inverse electron-demand Diels-Alder adducts. Several adducts derived from 8-N,N-dimethylaminomethyl-substituted isoflavonoids displayed good activity in the 1-10 μM concentration range in an in vitro proliferation assay using the PC-3 prostate cancer cell line.

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“…The compounds were prepared by the procedure depicted in Scheme . The starting material, 4‐oxo‐4 H ‐chromene‐3‐carbonyl chloride 1 was synthesized from 4‐oxo‐4 H ‐chromene‐3‐carbaldehyde obtained by Wilsmeier – Haack reaction, according to published procedures 10–12. 4‐Oxo‐4 H ‐1‐benzopyran‐3‐carboxylic acid 2 was prepared by hydrolysis of 4‐oxo‐4 H ‐chromene‐3‐carbonyl chloride 1 , whereas condensation of 1 with methanol at room temperature gave methyl 4‐oxo‐4 H ‐1‐benzopyran‐3‐carboxylate 3 .…”

Section: Resultsmentioning

confidence: 99%

Synthesis and Biological Evaluation of New Bischromone Derivatives with Antiproliferative Activity

Szulawska-Mroczek

Szumilak

Szczesio

et al. 2012

Archiv der Pharmazie

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The synthesis of new bischromone derivatives (4a-c and 5a-c) as potential anticancer drugs is described. The difference in the reactivity between 4-oxo-4H-chromene-3-carboxylic acid 2 (or its methyl ester 3) and 4-oxo-4H-chromene-3-carbonyl chloride 1 with three different polyamines: 3,3'-diamino-N-methyldipropylamine (a), 1,4-bis(3-aminopropyl)piperazine (b), 4,9-dioxa-1,12-dodecanediamine (c) resulted in the formation of two different groups of products, compounds 4a-c and 5a-c, designed in agreement with the bisintercalators' structural requirements. The transformation of 4-oxo-4H-chromene-3-carboxylic acid into 2H-chromene-2,4(3H)-diones (5) was confirmed by the NMR and XRD experiments. Compounds 4a and 5a were evaluated in vitro in the highly aggressive melanoma cell line A375. An enhanced induction of apoptosis and cell cycle arrest clearly revealed that compound 5a was more potent than 4a. Compound 5a was also more active in diminishing the adhesive potential of melanoma cells. Current studies support the notion that small changes in the three-dimensional structure of molecules might have a substantial impact on their biological activity.

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Cycloadditions of substituted benzopyran-4-ones to electron-rich dienes: a new route to xanthone derivatives

Cited by 61 publications

References 24 publications

Nucleophilic Addition Reaction with Dearomatization of Naphthalene Ring

Nucleophilic Addition Reaction with Dearomatization of Naphthalene Ring

Antineoplastic Isoflavonoids Derived from Intermediate ortho‐Quinone Methides Generated from Mannich Bases

Synthesis and Biological Evaluation of New Bischromone Derivatives with Antiproliferative Activity

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