37620-37-4Relevant articles and documents
Synthesis of lithium/cesium-Zagronas from zagrosian natural asphalt and study of their activity as novel, green, heterogeneous and homogeneous nanocatalysts in the Claisen–Schmidt and Knoevenagel condensations
Soleiman-Beigi, Mohammad,Ghalavand, Saba,Venovel, Hadis Gholami,Kohzadi, Homa
, p. 3267 - 3279 (2021/06/17)
A novel, heterogeneous and homogeneous basic nanocatalysts were synthesized by grafting of lithium and cesium on zagrosian natural asphalt sulfonate (Li/Cs-Zagronas). The activity of these catalysts was examined in the Claisen–Schmidt and Knoevenagel condensations under mild reaction conditions. Li/Cs-Zagronas were characterized by FT-IR spectroscopy, scanning electron microscopy, X-ray diffraction, energy-dispersive spectroscopy, inductively coupled plasma and thermogravimetric analysis techniques. These nanocatalysts were removed by simple filtration and reused several times without any deterioration of activity.
Novel potent and selective DPP-4 inhibitors: Design, synthesis and molecular docking study of dihydropyrimidine phthalimide hybrids
Mourad, Ahmed A. E.,Khodir, Ahmed E.,Saber, Sameh,Mourad, Mai A. E.
, p. 1 - 24 (2021/02/26)
Background: Dipeptidyl peptidase-4 (DPP-4) inhibitors have emerged as antihyperglycemic agents that improve glycemic control in type 2 diabetic patients, either as monotherapy or in combination with other antidiabetic drugs. Methods: A novel series of dihydropyrimidine phthalimide hybrids was synthesized and evaluated for their in vitro and in vivo DPP-4 inhibition activity and selectivity using alogliptin as reference. Oral glucose tolerance test was assessed in type 2 diabetic rats after chronic treatment with the synthesized hybrids ± metformin. Cytotoxicity and antioxidant assays were performed. Additionally, molecular docking study with DPP-4 and structure activity relationship of the novel hybrids were also studied. Results: Among the synthesized hybrids, 10g, 10i, 10e, 10d and 10b had stronger in vitro DPP-4 inhibitory activity than alogliptin. Moreover, an in vivo DPP-4 inhibition assay revealed that 10g and 10i have the strongest and the most extended blood DPP-4 inhibitory activity compared to alogliptin. In type 2 diabetic rats, hybrids 10g, 10i and 10e exhibited better glycemic control than alogliptin, an effect that further supported by metformin combination. Finally, 10j, 10e, 10h and 10d had the highest radical scavenging activity in DPPH assay. Conclusions: Hybrids 10g, 10i and 10e are potent DPP-4 inhibitors which may be beneficial for T2DM treatment.
Chalcones and bis-chalcones analogs as DPPH and ABTS radical scavengers
Bale, Adebayo Tajudeen,Salar, Uzma,Khan, Khalid Mohammed,Chigurupati, Sridevi,Fasina, Tolulope,Ali, Farman,Ali, Muhammad,Sekhar Nanda, Sitansu,Taha, Muhammad,Perveen, Shahnaz
, p. 249 - 257 (2021/04/21)
Background: A number of synthetic scaffolds, along with natural products, have been identified as potent antioxidants. The present study deals with the evaluation of varyingly substituted, medicinally distinct class of compounds “chalcones and bis-chalcon
Synthesis of chalcone derivatives by phthalhydrazide-functionalized tio2-coated nano-fe3o4 as a new heterogeneous catalyst
Farahi, Mahnaz,Karami, Bahador,Keshavarz, Raziyeh,Nia, Forough Motamedi
, p. 407 - 414 (2021/09/07)
Phthalhydrazide immobilized on TiO2-coated nano Fe3O4 (Fe3O4-P) was synthesized and characterized by FT-IR, XRD, SEM, EDS and VSM analysis. The resulting magnetic nanocatalyst was used as a catalyst for the synthesis of chalcone derivatives which affords the desired products in good to excellent yields. This catalyst can be isolated readily after completion of the reaction by an external magnetite field and reused several times without significant loss of activity.
Bu4NHSO4-Catalyzed Direct N-Allylation of Pyrazole and its Derivatives with Allylic Alcohols in Water: A Metal-Free, Recyclable and Sustainable System
Zhuang, Hongfeng,Lu, Nan,Ji, Na,Han, Feng,Miao, Chengxia
supporting information, p. 5461 - 5472 (2021/09/29)
Allylic amines are valuable and functional building blocks. Direct N-allylation of pyrazole and its derivatives as an atom economic strategy to provide allylic amines has been achieved only using commercial Bu4NHSO4 as the metal-free catalyst and water as the solvent without any additives. 11–93% isolated yields were obtained for the N-allylation of pyrazole and its derivatives with allylic alcohols. Bu4NHSO4 could be reused for six times by simple extraction nearly without loss of catalytic activity and was also suitable for a gram-scale production. The reaction of allylic ether and pyrazole did not occur to give the desired product indicated that allylic ether was not the active intermediate in the pathway. Density functional theory (DFT) calculations reveal that there are hydrogen bonding effects among substrates, solvent and catalyst, especially the one formed between allylic alcohol and H2O. Control experiments in different protic solvents further demonstrate the intermolecular hydrogen bonding of allylic alcohol and water. (Figure presented.).
Synthesis, characterization, in vitro cholinesterase and hRBCs hemolysis assay and computational evaluation of novel 2,3,4,5-tetrahydrobenzothiazepine appended α-aminophosphonates
Shaikh, Sarfaraz,Dhavan, Pratik,Uparkar, Jasmin,Singh, Pinky,Vaidya,Jadhav,Ramana
, (2021/10/12)
A series of novel 2,3,4,5-tetrahydrobenzothiazepine appended α-aminophosphonate derivatives were synthesized by subjecting 2,3-dihydrobenzothiazepine to Pudovik reaction using diethyl phosphite. Tested derivatives exhibited better AChE inhibition (0.86–12
Design, synthesis and evaluation of 2,4,6-substituted pyrimidine derivatives as BACE-1 inhibitor: Plausible lead for alzheimer’s disease
Jadhav, Hemant R.,Jain, Priti,Wadhwa, Pankaj K.
, p. 1194 - 1206 (2021/12/21)
Alzheimer’s disease is one of the most common neurodegenerative disorder afflicting a large mass of population. BACE-1 (β-secretase) is an aspartyl protease of the amyloidogenic pathway considered responsible for Alzheimer’s disease (AD). Since it catalyzes the rate-limiting step of Aβ-42 production from amyloid precursor protein (APP), its inhibition is considered a viable thera-peutic strategy. We have reported the design of small molecular weight compounds supposed to be blood brain permeable as BACE-1 inhibitors. The clue for the design of this series is drawn from the previously designed series from our research group. Objective: Design and synthesis of 2,4,6-substituted pyrimidine derivatives has been reported. In vitro FRET-based screening of synthesized derivatives was performed to evaluate the BACE-1 inhibition profile. Methods: Based on the docking simulation studies, a library of derivatives was designed, synthesized and evaluated for BACE-1 inhibition in-vitro. The docking studies were performed on Glide (Schrodinger suite) and Molegro virtual docker. Theoretical toxicity was predicted using Osiris Property Explorer. The synthesized compounds were tested for BACE-1 inhibition using in vitro assay based on Fluorescence Resonance Energy Transfer technique. The percent inhibition was cal-culated as a measure of activity. Results: The designed compounds revealed strong interactions with the desired amino acids of BACE-1 active sites. The aromatic rings placed at the fourth and sixth position of the pyrimidine ring occupied S1 and S3 substrate-binding clefts while the amino group formed hydrogen bonding interactions with Asp32 and Asp228. In silico data ensured that the compounds were orally bioavailable and brain permeable. The in vitro testing showed that the compounds inhibited BACE-1 at 10μM concentration. Conclusion: Compounds substituted with m-benzyloxy on one aromatic ring and o,p-di-chloro on another aromatic ring displayed maximum BACE-1 inhibition. Compound 2.13A displayed high docking score and was found to be most potent with IC50 of 6.92μM. The series displayed a good correlation between the docking score and BACE-1 inhibition profile.
N-Heterocyclic Carbene Catalyzed Synthesis of Trisubstituted Epoxides via Tandem Amidation/Epoxidation Sequence
Devi, E. Sankari,Pavithra, Thangavel,Tamilselvi,Nagarajan, Subbiah,Sridharan, Vellaisamy,Maheswari, C. Uma
supporting information, p. 3576 - 3580 (2020/04/20)
A tandem amidation/epoxidation sequence between various substituted chalcones and N,N-dimethylformamide (DMF) for the synthesis of trisubstituted epoxides employing N-heterocyclic carbene catalysis was developed. This reaction was performed under metal-free conditions in the presence of tert-butyl hydroperoxide (TBHP) as the oxidant. Trisubstituted epoxides bearing a ketone and an amide functionality (N,N-dimethyl formyl group) were synthesized starting from a wide range of chalcones in moderate to good yields with excellent diastereoselectivity.
Lewis acid catalyst system for Claisen-Schmidt reaction under solvent free condition
Halpani, Chandni G.,Mishra, Satyendra
, (2020/07/16)
Ca(OTf)2 in combination with NBu4.BF4 was established to function as an efficient catalyst system for one-pot Claisen-Schmidt condensation under neat conditions. Substituted acetophenones and benzaldehydes were coupled in situ to afford their corresponding chalcones in excellent yields. The method, with a broad range of substrate tolerance and mild operational conditions can produce assorted chalcone derivatives in moderate to high yields from easily accessible starting materials.
Potassium Natural Asphalt Sulfonate (K-NAS): Synthesis and characterization as a new recyclable solid basic nanocatalyst and its application in the formation of carbon–carbon bonds
Falah, Saeid,Soleiman-Beigi, Mohammad,Kohzadi, Homa
, (2020/07/06)
In this research, we synthesized and characterized a new heterogeneous basic nanocatalyst and its catalytic application was studied in the Claisen-Schmidt and Knoevenagel condensations. In order to prepare this nanocatalyst, first, the Iranian natural asphalt was sulfonated with the concentrated sulfuric acid and then, converted to the potassium natural asphalt sulfonate (K-NAS). In order to characterization of the nanocatalyst, used of FT-IR spectroscopy, scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS), X-ray diffraction (XRD), inductively coupled plasma (ICP) and thermogravimetric analysis (TGA) techniques. This new basic heterogeneous nanocatalyst have advantages such as being eco-friendly, huge specific surface area, high reactivity and recyclability.
