Mono-carbonyl Analogues Research Articles

Synthesis and Biological Evaluations of Monocarbonyl Curcumin Inspired Pyrazole Analogues as Potential Anti-Colon Cancer Agent.

PurposeThe monocarbonyl analogs of curcumin (MCACs) have been widely studied for their promising antitumor activity. Pyrazole is a five-membered aromatic heterocyclic system with various bioactivities incorporated frequently in drugs. However, few of MCACs inspired pyrazole analogues were investigated. To search for more potent cytotoxic agents based on MCACs, a series of new 1,5-diaryl/heteroaryl-1,4-pentadien-3-ones inspired pyrazole moiety was synthesized and evaluated on their anti-colon cancer activities.MethodsFifteen new compounds were synthesized and characterized by spectral datum, and then they were tested preliminarily by MTT assay for their cytotoxic activities against a panel of four human cancer cell lines, namely, gastric (SGC-7901), liver (HepG2), lung (A549), and colon (SW620) cancer cells. Compound 7h exhibited excellent selectivity and outstanding anti-proliferation activity against SW620 cells among these 15 compounds. Further, the mechanisms were investigated by transwell migration and invasion assay, clonogenic assay, cell apoptosis analysis, cell cycle analysis, Western blot analysis.ResultsThe IC50 value of 7h against SW620 cells was 12 nM, being more potent than curcumin (IC50 = 9.36 μM), adriamysin (IC50 = 3.28 μM) and oxaliplatin (IC50 = 13.33 μM). Further assays showed that 7h inhibited SW620 cell migration, invasion and colony formation obviously, which was due to its ability to induce cell cycle arrest in the G2/M and S phases and apoptosis. Western blot assay revealed that 7h decreased the protein expression of ATM gene, which may primarily contribute to its anticancer activity against SW620 cells.ConclusionA new MCACs 7h was synthesized and found to exhibit excellent anti-proliferation activity against SW620 cells. Further studies indicated that 7h exerted its anticancer activity against SW620 cells probably via decreasing the ATM protein expression. The present study suggested that 7h was a promising candidate as an anti-colon cancer drug for future development.

Quinoline Based Monocarbonyl Curcumin Analogs as Potential Antifungal and Antioxidant Agents: Synthesis, Bioevaluation and Molecular Docking Study.

In search for new fungicidal and free radical scavenging agents, we synthesized a focused library of 2-chloroquinoline based monocarbonyl analogs of curcumin (MACs). The synthesized MACs were evaluated for in vitro antifungal and antioxidant activity. The antifungal activity was evaluated against five different fungal strains such as Candida albicans, Fusarium oxysporum, Aspergillus flavus, Aspergillus niger, and Cryptococcus neoformans, respectively. Most of the synthesized MACs displayed promising antifungal activity compared to the standard drug Miconazole. Furthermore, molecular docking study on a crucial fungal enzyme sterol 14α-demethylase (CYP51) could provide insight into the plausible mechanism of antifungal activity. MACs were also screened for in vitro radical scavenging activity using butylated hydroxytoluene (BHT) as a standard. Almost all MACs exhibited better antioxidant activity compared to BHT.

Allylated Curcumin Analog CA6 Inhibits TrxR1 and Leads to ROS-Dependent Apoptotic Cell Death in Gastric Cancer Through Akt-FoxO3a.

BackgroundGastric cancer is one of the leading causes of cancer-related deaths. Allylated monocarbonyl analogs of curcumin (MACs) have been reported to selectively inhibit a broad range of human cancers including gastric cancer. However, the precise molecular mechanisms underlying the inhibitory activities of MACs are not fully known.MethodsIn this study, we examined the anti-tumor activities of an allylated MAC, CA6, on gastric cancer cells and gastric cancer xenograft mouse model. The potential molecular anti-tumor mechanisms of CA6 were also elucidated.ResultsOur data show that CA6 exhibited significant cytotoxicity in gastric cancer cells, which was seen as an induction of G2/M cell cycle arrest and apoptosis. These activities were mediated through an elaboration of ROS levels in gastric cancer cells and induction of endoplasmic reticulum stress. CA6 increased ROS levels through directly binding to and inhibiting thioredoxin reductase R1 (TrxR1). Also, CA6-generated ROS inhibited Akt and activated forkhead O3A (FoxO3a), causing cytotoxicity in gastric cancer cells. Finally, CA6 treatment dose-dependently reduced the growth of gastric cancer xenografts in tumor-bearing mice, which was associated with reduced TrxR1 activity and increased ROS in the tumor.ConclusionIn summary, our studies demonstrate that CA6 inhibited gastric cancer growth by inhibiting TrxR1 and increasing ROS, which in turn activated FoxO3a through suppressing Akt. CA6 is a potential candidate for the treatment of gastric cancer.

Curcumin Analogs Reduce Stress and Inflammation Indices in Experimental Models of Diabetes.

Chronic inflammation and oxidative stress lead to a multitude of adverse cellular responses in target organs of chronic diabetic complications. Curcumin, a highly investigated phytochemical, has been shown to exhibit both anti-inflammatory and antioxidant activities. However, the clinical application of curcumin has been greatly limited due to a poor pharmacokinetic profile. To overcome these limitations, we have generated analogs of curcumin to enhance bioavailability and offer a preferable pharmacokinetic profile. Here, we explored the effects of two mono-carbonyl curcumin analogs, L2H21 and L50H46, in alleviating indices of inflammation and oxidative stress in cell culture and mouse model of diabetic complications. Our results show that L2H21 and L50H46 normalize inflammatory mediators (IL-6 and TNF-α), extracellular matrix proteins (FN and COL4α1), vasoactive factors (VEGF and ET-1) and a key transcriptional coactivator (p300) in cultured human retinal microvascular endothelial cells (HRECs) and dermal-derived microvascular endothelial cells (HMVECs) challenged with high levels of glucose. These curcumin analogs also reduced glucose-induced oxidative DNA damage as evidenced by 8-OHdG labeling. We further show that treatment of streptozotocin-induced diabetic mice with curcumin analogs prevents cardiac and renal dysfunction. The preservation of target tissue function was associated with normalization of pro-inflammatory cytokines and matrix proteins. Collectively, our results show that L2H21 and L50H46 offer the anti-inflammatory and antioxidant activities as has been reported for curcumin, and may provide a clinically applicable therapeutic option for the treatment of diabetic complications.

Cytochrome P450-Mediated Metabolic Characterization of a Mono-Carbonyl Curcumin Analog WZ35

WZ35 is a monocarbonyl analog of curcumin, which had been proved advantage over curcumin in chemical stability and antitumor activity. However, its pharmacokinetic profile has not been determined. In the present study, an ultraperformance liquid chromatography-tandem mass spectrometry assay was developed to detect concentration of WZ35 in rat plasma. Subsequently, pharmacokinetic study showed that the oral bioavailability of WZ35 is 10.56%. Cytochrome P450 (CYP450) plays a major role in metabolizing exogenous substance. The concentration of WZ35 was sharply decreased while incubating with microsome. It’s indicated that WZ35 is a substrate of CYP450s. Molecular docking assay showed that WZ35 can combine with CYP2B6 and CYP2C9 to form much more stable complex. The lowest docking energy was generated in complex with CYP2E1. The inhibition of CYP450s by WZ35 was also evaluated. Pan inhibitions of WZ35 on rat CYP3A2, CYP2B1, CYP2C11, CYP2D1, and ­CYP2E1 were observed by detecting probe substrates (midazolam, bupropion, tolbutamide, dextromethorphan, chlorzoxazone) and metabolites accordingly. On an average, 80% activities of enzymes were blocked. Mechanistically, the inhibitions of WZ35 on CYP3A2, CYP2B1, CYP2E1 were in a time-dependent manner according to the results of IC₅₀ shift assay. The collective data demonstrated that the oral bioavailability of monocarbonyl analog of curcumin has significantly improved compared to curcumin. It’s both the substrate and inhibitor of CYP450s through in a time-dependent mechanism.

Design, synthesis and preliminary in-vitro studies of novel boronated monocarbonyl analogues of Curcumin (BMAC) for antitumor and β-amiloyd disaggregation activity

Curcumin is currently being investigated for its capacity to treat many types of cancer and to prevent the neuron damage that is observed in Alzheimer’s disease (AD). However, its clinical use is limited by its low stability and solubility in aqueous solutions. In this study, we propose a completely new class of boronated monocarbonyl analogues of Curcumin (BMAC, 6a-c), in which a carbonyl group replaces the Curcumin β-diketone functionality, and an ortho-carborane, an icosahedral boron cluster, substitutes one of the two phenolic rings. BMAC antitumor activity against MCF7 and OVCAR-3 cell lines was assessed in vitro and compared to that of Curcumin and the corresponding MAC derivative. BMAC 6a-c showed efficiencies that are comparable to that of MAC and superior to that of Curcumin in both the cell lines. Moreover, the inhibition of the formation of β-amyloid aggregates by BMAC 6a-c was evaluated and it was shown that compound 6c, which contains two OH moieties, has a better efficiency than Curcumin. The presence of a second –OH group can enhance the compound’s binding efficacy with β-amyloid aggregates. For the future, the presence of at least one carborane group means that the BMAC antitumor effect can be coupled with Boron Neutron Capture Therapy.

Ruthenium arene complexes with mono-carbonyl analogues of curcumin as pendant or bridging ligands: Synthesis, anti-cancer activity and interaction with quadruplex DNA

Four ruthenium(II) arene complexes containing mono-carbonyl analogues of curcumin (MAC) functioning as pendant or bridging ligands as well as chlorido ancillary ligands have been synthesized and structurally characterized by IR and 1H NMR spectroscopies, ESI mass spectrometry and elemental analysis. Anti-proliferative activity of the complexes determined on MOLT-4 human leukemia cells revealed good to moderate activity. Two of the compounds, 3b and 4b, both of which incorporated cyclohexanone as part of the MAC structural motif, displayed potency comparable to cisplatin. In intercalative binding studies, while the organic MACs did not display any interaction with quadruplex DNA, the ruthenium complexes were found to be able to stabilize quadruplex DNA, with 3b and 4b displaying the greatest selectivity for HTelo over c-myc. Compound 4b, in which the MAC ligand is bridged by two organoruthenium centres, bound to HTelo more tightly than 3b, in which the MAC functions as a pendant ligand towards a single ruthenium arene core. These results suggest that minor changes to the structural motif of the MAC ligand, as well as the presence of the ruthenium arene moiety play an important role in achieving selective quadruplex DNA stabilization.

Monocarbonyl curcumin analog A2 potently inhibits angiogenesis by inducing ROS-dependent endothelial cell death.

Excessive and abnormal vessel growth plays a critical role in the pathogenesis of many diseases, such as cancer. Angiogenesis is one of the hallmarks of cancer growth, invasion, and metastasis. Discovery of novel antiangiogenic agents would provide new insights into the mechanisms of angiogenesis, as well as potential drugs for cancer treatment. In the present study, we investigated the antiangiogenic activity of a series of monocarbonyl analogs of curcumin synthesized previously in our lab. We found that curcumin analog A2 displayed the full potential to be developed as a novel antiangiogenic agent. Curcumin analog A2 at and above 20 μM dramatically inhibited the migration and tube formation of human umbilical vein endothelial cells (HUVECs) in vitro, new microvessels sprouting from the rat aortic rings ex vivo and newly formed microvessels in chicken chorioallantoic membranes (CAMs) and Matrigel plus in vivo. We further demonstrated that curcumin analog A2 exerted its antiangiogenic activity mainly through inducing endothelial cell death via elevating NADH/NADPH oxidase-derived ROS. Curcumin analog A2 at the antiangiogenic concentrations also triggered autophagy in HUVECs, but this process is neither a pre-requisite for toxicity, leading to the cell death nor a protective response against the toxicity of curcumin analog A2. In conclusion, we demonstrate for the first time the potent antiangiogenic activity of the monocarbonyl curcumin analog A2, which could serve as a promising potential therapeutic agent for the prevention and treatment angiogenesis-related diseases, such as cancer.

Synthesis and evaluation of pyrazole‐incorporated monocarbonyl curcumin analogues as antiproliferative and antioxidant agents

A series of pyrazole‐incorporated monocarbonyl analogues of curcumin were synthesized via Clasien–Schimidt‐type condensation and subsequently screened for in vitro antiproliferative and antioxidant activity. The analogues 4c, 5d, 5e, 5g, 6e, and 6f showed potential activity against the MDA‐MB‐231 cell line. The synthesized analogues were also screened for their antioxidant activity. Compounds 5a, 5e, 6d, and 6f exhibit comparable radical scavenging activity with respect to the standard drug ascorbic acid. Furthermore, a molecular docking study has been conducted for 5d and 5g and suggests that these compounds have a potential to become lead molecules in drug discovery and process.

Curcumin Analogue C1 Promotes Hex and Gal Recruitment to the Plasma Membrane via mTORC1-Independent TFEB Activation.

The monocarbonyl analogue of curcumin (1E,4E)-1,5-Bis(2-methoxyphenyl)penta-1,4-dien-3-one (C1) has been used as a specific activator of the master gene transcription factor EB (TFEB) to correlate the activation of this nuclear factor with the increased activity of lysosomal glycohydrolases and their recruitment to the cell surface. The presence of active lysosomal glycohydrolases associated with the lipid microdomains has been extensively demonstrated, and their role in glycosphingolipid (GSL) remodeling in both physiological and pathological conditions, such as neurodegenerative disorders, has been suggested. Here, we demonstrate that Jurkat cell stimulation elicits TFEB nuclear translocation and an increase of both the expression of hexosaminidase subunit beta (HEXB), hexosaminidase subunit alpha (HEXA), and galactosidase beta 1 (GLB1) genes, and the recruitment of β-hexosaminidase (Hex, EC 3.2.1.52) and β-galactosidase (Gal, EC 3.2.1.23) on lipid microdomains. Treatment of Jurkat cells with the curcumin analogue C1 also resulted in an increase of both lysosomal glycohydrolase activity and their targeting to the cell surface. Similar effects of C1 on lysosomal glycohydrolase expression and their recruitment to lipid microdomains was observed by treating the SH-SY5Y neuroblastoma cell line; the effects of C1 treatment were abolished by TFEB silencing. Together, these results clearly demonstrate the existence of a direct link between TFEB nuclear translocation and the transport of Hex and Gal from lysosomes to the plasma membrane.

Antiparasitic activity of synthetic curcumin monocarbonyl analogues against Trichomonas vaginalis

Trichomoniasis is a parasitic infection caused by Trichomonas vaginalis and it is considered to be the most common non-viral sexually transmitted infection in the world. Since the 1960s, nitroimidazoles such as metronidazole are the drugs of choice for the treatment of trichomoniasis, but many adverse effects and allergic reactions may result from their use. Reports of metronidazole-resistant infections also highlight the importance for the search of new anti-T. vaginalis agents. Considering this, herein we report the anti-T. vaginalis evaluation of 21 synthetic monocarbonyl analogues of curcumin, which itself has been reported to possess antiparasitic potential. From the in vitro analysis of the synthetic molecules, untreated trophozoites, and metronidazole at 100 μM, it was observed that three curcumin analogues (3a, 3e, and 5e) exhibited anti-T. vaginalis activity comparable to metronidazole (no significant statistical difference). Optimal antiparasitic concentrations were determined to be 80 μM and 90 μM for propanone derivatives 3a and 3e, respectively, and 200 μM for cyclohexanone derivative 5e. Kinetic growth curves showed that, after 24 h, the trophozoites were completely inhibited. At the tested concentrations, natural curcumin did not significantly inhibit the growth of trophozoites, therefore demonstrating that the designed synthetic molecules not only have better chemical stability, but also higher anti-T. vaginalis potential. Cytotoxicity analysis, performed on VERO cells, demonstrated low, moderate and high cytotoxic effects for analogues 3e, 5e and 3a, respectively. This study suggests that these analogues possess chemical features of interest to be further explored as alternatives for the treatment of trichomoniasis.

Inhibition of breast cancer metastasis to the lungs with UBS109.

Synthetic monocarbonyl analogs of curcumin (MACs) are cytotoxic against several cancers including head and neck cancer, pancreatic cancer, colon cancer, and breast cancer. Mechanisms of action include depolarization of the mitochondrial membrane potential and inhibition of NF-κB, leading to apoptosis. We previously demonstrated that UBS109 (MAC), has preventive effects on bone loss induced by breast cancer cell lines. We determined whether UBS109 could inhibit and prevent lung metastasis, since lung metastasis of breast cancer is a major problem in addition to bone metastasis. A breast cancer lung metastasis (colonization) model was created by injection of breast cancer cells MDA-MB-231 into the tail vein of athymic nude mice, nu/nu. Animals were treated with vehicle or UBS109 at 5 or 15 mg/kg body weight by intraperitoneal injection once daily 5 days a week for 5 weeks. UBS109 at 15 mg/kg significantly inhibited lung metastasis/colonization as demonstrated by reduced lung weight consisting of tumor nodules. The body weight of animals treated with UBS109 15 mg/kg remained the same as in the other groups. UBS109 killed completely (100%) MDA-MB-231 breast cancer cells at 1.25 μM in a cytotoxicity assay in vitro. UBS109 15 mg/kg i.p. showed a maximal blood concentration (Cmax) of 432 ± 387 ng/mL at 15 min post injection. This is approximately 1.5 ng/ml in the blood of mice and equals 1.5 μM of UBS109. These in vitro and in vivo results are consistent with each other.

Synthesis, Antimalarial Activity, and Docking Studies of Monocarbonyl Analogues of Curcumin

Abstract The synthesis of five monocarbonyl analogues of curcumin is described. In vitro anti-malarial assay of the compounds was carried out and the effect of the substituents on the aryl ring has been described. The results show that all the five compounds exhibited some reasonable activity against the chloroquine-resistant plasmodium parasite. Molecular docking studies further confirmed the observed biological activity of the compounds.

A mono-carbonyl analog of curcumin induces apoptosis in drug-resistant EGFR-mutant lung cancer through the generation of oxidative stress and mitochondrial dysfunction.

IntroductionTargeted therapies using epidermal growth factor receptor-tyrosine kinase inhibitors (EGFR-TKIs) have revolutionized the treatment of non-small cell lung cancer (NSCLC) patients harboring EGFR mutations, leading to the approval of gefitinib and erlotinib as standard first-line clinical treatment. Inevitably, a considerable proportion of patients develop resistance to EGFR-TKIs due to the acquisition of secondary mutations within EGFR. Therefore, alternative strategies to target NSCLC are desperately needed.Materials and methodsIn this study, we have evaluated the effect of a reactive oxygen species (ROS)-inducing agent WZ35, a mono-carbonyl analog of curcumin, to target an inherent biological property of cancer cells, increased oxidative stress. To study whether WZ35 can inhibit NSCLC tumorigenesis, we used gefitinib- and erlotinib-resistant cell line H1975.ResultsIn this study, we show that WZ35 treatment dramatically decreases cell viability and induces apoptosis in H1975 cells through the generation of ROS. We also found that the antitumor activity of WZ35 involved ROS-mediated activation of the endoplasmic reticulum stress pathway and mitochondrial dysfunction. Furthermore, WZ35 significantly inhibited H1975 xenograft tumor growth through the inhibition of cell proliferation and induction of apoptosis.DiscussionThese findings show that WZ35 may be a promising candidate for the treatment of EGFR-TKI-resistant NSCLC.

Synthesis and Cytotoxicity Evaluation of Novel Asymmetrical Mono-Carbonyl Analogs of Curcumin (AMACs) against Vero, HeLa, and MCF7 Cell Lines.

A series of novel asymmetrical mono-carbonyl analogs of curcumin (AMACs) were synthesized and evaluated for cytotoxic activity using BSLT and MTT assay against Vero, HeLa, and MCF7 cell lines. The structures of the synthesized compounds were confirmed by FTIR, 1H-NMR, 13C-NMR, and mass spectral data. The results of the cytotoxicity evaluation showed that the synthesized compounds exhibited moderate to very high toxic activity in BSLT (LC50 value 29.80–1704.23 µM); most of the compound exhibited cytotoxic activity against HeLa cell lines, which is comparable to the activity of cisplatin (IC50 value 40.65–95.55 µM), and most of the compound tested against MCF7 cell lines exhibited moderate to very high cytotoxic activity (IC50 value 7.86–35.88 µM). However, the selectivity index (SI) of the compounds was low (<1–1.96). Among the synthesized compounds, compound 1b was the most cytotoxic and selective against MCF7 cell lines. It could be considered for further development to obtain the more active and selective chemotherapeutic agents against breast cancer.

Mono-carbonyl analogues of curcumin prevents paraquat-induced apoptosis in HK-2 cell line by inhibiting oxidative damage and inflammation

Objective: To investigate the effects of mono-carbonyl analogues of curcumin (L6H21) on paraquat (PQ) -induced injury in HK-2 cell line and explore its underlying mechanisms. Methods: Cultured HK-2 cells were challenged by PQ with or without L6H21 treatment. Cell viability and apoptosis were determined by CCK-8 assay and flow cytometry, respectively. Gene expressions and protein levels of apoptotic and inflammatory factors were assessed by RT-PCR, ELISA, and western blot. Intracellular ROS production was detected by DCFH-DA staining. Superoxide dismutase (SOD) and malondialdehyde (MDA) were examined by chemical colorimetry. Results: 1) PQ challenge significantly inhibited HK-2 cells proliferation, which was prevented by L6H21 administration. PQ dramatically induced HK-2 apoptosis evidenced by increasing expressions of caspase-9, caspase-3 and Bax, while decreasing Bcl-2 level. However, PQ induced these apoptotic effects in HK-2 cells were reversed by L6H21. Similarly, PQ exposure obviously enhanced activity of NF-κB and levels of cytokines (TNF-α、IL-6) in HK-2 cells, which was inhibited by L6H21. Furthermore, administration of L6H21 inhibited PQ induced ROS and MDA production, and promoted SOD level in HK-2 cells. Conclusion: L6H21 administration inhibits PQ-induced apoptosis in HK-2 cells possibly by reducing inflammation and oxidative damage.

Novel allylated monocarbonyl analogs of curcumin induce mitotic arrest and apoptosis by reactive oxygen species-mediated endoplasmic reticulum stress and inhibition of STAT3.

Curcumin is a promising active compound from a natural source and is extensively being tested in clinical trials because of its bio-functional properties. However, poor bioavailability has hampered its clinical application. Numerous attempts have been made in our laboratory to discover analogs of curcumin with enhanced bioavailability and superior pharmacological activity. In this study, we have investigated a new series of allylated monocarbonyl analogs of curcumin (MAC) and tested their effect on gastric cancer cells. Our results show six MAC that selectively targeted cancer cell lines to inhibit growth and induce apoptosis. This activity was achieved by generation of reactive oxygen species (ROS) by MAC. We selected one effective MAC (CA10) for further investigation and show that CA10 inhibits cell growth by causing G2/M cell cycle arrest and induction of apoptotic death. CA10 induced ROS generation and subsequent activation of endoplasmic reticulum (ER) stress and inhibition of signal transducer and activator of transcription 3 (STAT3) phosphorylation, inhibits cancer cell proliferation. These anti-tumor activities of CA10 were confirmed in gastric cancer xenografts. CA10 induced ROS, activated the ER stress pathway and inhibited STAT3 phosphorylation and gastric xenografts tumor growth in mice. Our studies provide experimental evidence that MAC CA10 effectively targets gastric cancer in preclinical models by enhancing ROS and ROS-mediated signaling.

3,5-Bis(2-fluorobenzylidene)-4-piperidone induce reactive oxygen species-mediated apoptosis in A549 cells

The presence of the substituents in the ortho position of the aromatic ring(s) is helpful to strenghen the biological activity, highlighting a so-called ortho effect. In this paper, we synthesized six mono-carbonyl curcumin analogs with the fluorine group, which imparts a variety of properties to certain medicines. Then, the cytotoxicity against A549 and NCI-H460 cells was evaluated by the MTT assay. The results exhibited that 1d surfaced as an important lead compound displaying almost 13-fold cytotoxicity relative to curcumin against A549 cells. More importantly, 1d was more stable and more massive uptake than curcumin, which may be relationship to their cytotoxicity, apoptotic acitivity and reactive oxygen species generation. The generation of reactive oxygen species is associated with falling apart in the redox buffering system, and subsequently induces lipid peroxidation, collapse of the mitochondrial membrane potential and ultimately leads to apoptosis. These data indicated that ortho effect and leading fluorine into medicine molecular are successful strategy to improve anticancer activity of mono-carbonyl curcumin analogs.

In-silico Antimalarial Study of Monocarbonyl Curcumin Analogs and Their 2,4-Dinitro Phenylhydrazones Using the Inhibition of Plasmepsin II as Test Model

A well-known component of the Indian spice turmeric, curcumin, has received a lot of attention in recent years as a potential antimalarial agent but the inherent problems associated with low bioavailabilty tends to limit its applicability. The bioavailability is linked to its low solubility in water and its rapid break down in the blood plasma. In this study, we have proposed the use of synthetic analogs of curcumin and their derivatives which are expected to be less prone to degradation in the blood plasma as possible antimalarials. The binding affinity of monocarbonyl analogs of curcumin and their 2,4-dinitrophenylhydrazone derivatives for the chain A domain of plasmepsin II, one of the key enzymes involved in hemoglobin digestion in the food vacuole of the malaria parasite was determined by computational docking analysis, performed using Auto Dock Vina 1.1.2, pymol and Chem 3D ultra 12.0. The binding energies of the 20 compounds studied was compared with that of pepstatin A (a known inhibitor of plasmepsin II), curcumin and chloroquine. The 3D structure of the protein was obtained from the protein data bank (PDB ID:1M43), the compounds’ 3D structure was generated with the Chem 3D ultra 12.0 and visualization done with pymol. Out of the 20 compounds docked with plasmepsin II, 17 had binding energies higher than that of pep A (-32.6, kJ/mol) and 19 of the compounds had binding energies higher than that of curcumin (30.96, kJ/mol). The docked compounds, 5b, 6b and 7b had the highest binding energies (-44.73 kJ/mol, -42.64 kJ/mol and -41.80 kJ/mol respectively). It is expected that the compounds with binding energies higher than that of pep A may be considered for further antimalarial studies in-vitro and in-vivo.

Ultrasound-assisted Synthesis of Some New Curcumin Analogs and Their Corresponding Pyrazoline Derivatives

In this work, a series of new curcumin mono-carbonyl analogs containing benzyloxy moieties and their pyrazoline derivatives were synthesized using a green method (ultrasound assisted technique) along with traditional method. The work also includes a comparison between the two methods together and with literature. Remarkable improvements were achieved by dropping down the reaction time from hours to minutes and obtaining higher yields of the products.