Synthesis and antiallergic properties of some 4H,5H-pyrano[3,2-c][1]benzopyran-4-one, 4H,5H-[1]benzothiopyrano[4,3-b]pyran-4-one, and 1,4-dihydro-5H-[1]benzothiopyrano[4,3-b]pyridin-4-one derivatives

Abstract

A series of novel 2-carboxylic acids of the title ring systems has been synthesized from the corresponding 3-acetyl-4H-[1]benzopyran-4-one and benzothiopyran-4-one. These acids were examined for their ability to inhibit the rat passive cutaneous anaphylaxis; the pyridinone carboxylic acids 6 displayed a higher degree of iv and ip anaphylactic activities than their pyranone analogues 5. The potassium salt 5a (R6 = K) was the only compound that exhibited a moderate oral activity.

Optimization of 1,2,3,4-Tetrahydroacridin-9(10H)-ones as Antimalarials Utilizing Structure–Activity and Structure–Property Relationships

“…Similarly, this compound provides a different class of ethers as opposed to THAs 62 , 70 , 73 , and 89 – 93 , which contain alkyl ether substituents. Sulfoxide 101 and sulfone 102 were oxidized from THA 92 using aqueous hydrogen peroxide at 40 °C and m -CPBA in CHCl 3 at 0 °C, respectively . Finally, a small set of THAs was prepared in which the 2-position possessed a difluoromethylene unit.…”

Construction of Chiral Isotetronic Acid-Fused Thiochromane via Doubly Annulative Strategy

“…For example, the pyridinone carboxylic acid 1a displayed a high degree of antianaphylactic activity (Figure ). Moreover, the benzothiopyran derivative 1b was a very potent full agonist at dopamine D2 receptors and a partial agonist at dopamine D3 receptors . In addition, compound 1c showed a 192-fold more powerful acetylcholinesterase (AChE) inhibitory activity than its oxygen-containing analogues, rivastigmine, thereby possessing great potential for the treatment of Alzheimer’s disease .…”

Development of Conjugate Addition of Lithium Dialkylcuprates to Thiochromones: Synthesis of 2-Alkylthiochroman-4-ones and Additional Synthetic Applications

“…Sulfur-containing heterocycles, such as thiochromanone, thioflavanone, thiochromone, thioflavone, and their derivatives ( Scheme 1 ) have been reported to display rich biological activities. For example, thioflavonoids, which are the sulfur analogues of flavonoids [ 12 , 13 , 14 , 15 , 16 , 17 , 18 ], display many biological activities, such as antimicrobial, antioxidant, inhibiting nitric oxide production, and antifungal et al [ 3 , 19 , 20 , 21 , 22 , 23 , 24 , 25 , 26 , 27 ] Thiochroman-4-ones have been reported to display antifungal activities. Some thiochroman-4-one derivatives have been studied and shown to display the cytotoxic effect on tumor cells in vitro [ 28 ].…”

“…They are key precursors for certain bioactive antiproliferative agents [ 31 ]. Known as an important class of heterocycles [ 3 , 4 ], they are vital precursors of bioactive thiochroman-4-one 1,1-dioxanes, as well as benzothiazepins [ 20 , 21 , 32 , 33 , 34 , 35 , 36 , 37 , 38 ].…”