A green and convenient approach for the synthesis of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano[2,3-c]pyrazole-3-carboxylates via a one-pot, multi-component reaction in water

A Review on the Recent Multicomponent Synthesis of Pyranopyrazoles

“…In 2012, 40 a four-component catalyst-free synthesis of methyl 6-amino-5-cyano-4-aryl-2,4-dihydropyrano [2,3-c]pyrazole-3-carboxylates (7) in water was described (Scheme 5). This protocol involves reaction between dimethyl acetylenedicarboxylate, hydrazine hydrate, malononitrile, and aromatic aldehydes in water.…”

Ultrasound mediated green synthesis of pyrano[2,3-c]pyrazoles by using Mn doped ZrO2

“…Pyrazole derivatives have occupied a vital place in drug research because of their various biological and pharmacological activities such as antibacterial (Tanitame et al, 2004), antifungal (Ragavan et al, 2010), antioxidant (Daiane et al, 2014), anticancer , antileishmanial (Faria et al, 2013), hypotensive (Arya et al, 1969), antiallergenic (Parsia et al, 1981) activities etc. Subsequently, several reports for the synthesis of these compounds have been reported including the use of TEA (Litvinov et al, 2009), Per-6-ABCD (Kuppusamy and Kasi, 2010), (Javad et al, 2012), TEABr (Kumar et al, 2007), [Dsim]AlCl 4 (Ahmad et al, 2013), FeNi 3 /SiO 2 /HPGMNP (Mohammad and Seyed, 2013), NaOH/microwave (Kathrotiya and Patel, 2012), Δ/reflux (Zonouz et al, 2012), Δ/CH 3 COOH (Gein et al, 2014), UV (Zou et al, 2011), Microwave (Sharma et al, 2016), Meglumine (Guo et al, 2013), Sproline (Khoobi et al, 2015), ZrO 2 (Saha et al, 2015), Fe 3 O 4 @SiO 2 (Soleimani et al, 2015), 1- (Bodhak et al, 2015) and SnO 2 (Paul et al, 2014). Several of these methods face few or more limitations such as, using expensive reagents and catalysts, strong acidic or basic conditions, toxic reagents, tedious steps, strict reaction conditions, low product yields and long reaction times, which limit their use in practical applications.…”

Recent Advance in Development of 3-Methyl-4-Arylmethylene Isoxazole-5(4h)-Ones and 6-Amino-1,4-Dihydropyrano[2,3-C]-Pyrazole-5-Carbonitriles: Synthetic Applications and Pathways

“…[20,21] Furthermore, 4H-Pyrans analogue heterocyclic scaffolds signify a privileged structural motif well distributed in naturally occurring compounds. [22] This important class of heterocyclic compounds displays a broad spectrum of biological activities such as anticancer [23] , anti-HIV [24] , anti-inflammatory [25] , antimalarial [26] , antimicrobial [27] , antiviral [28] , molluscicidal [29] , anticancer, fungicidal, analgesic, vasodilator, hypotensive, hypoglycaemic [30] , kinase inhibitor properties [31] and anti-proliferative. [32] Due to the importance of isoxazole-5(4H)-ones and pyrano [2,3- …”