2009 Volume 20 Issue 4

An efficient method to synthesize HMX by nitrolysis of DPT with N2O5 and a novel ionic liquid
Hui Zhen Zhi , Jun Luo , Guang An Feng , Chun Xu Lv
2009, 20(4): 379-382  doi: 10.1016/j.cclet.2008.12.040
[Abstract](207) [FullText HTML] [PDF 227KB](0)
A novel polyethylene glycol (PEG)-200-based dicationic acidic ionic liquid (PEG200-DAIL) was used to synthesize HMX from DPT by nitrolysis with N2O5. It was found that either N2O5 or PEG200-DAIL could improve the yield. Furthermore, the combined use of PEG200-DAIL and N2O5 could increase the yield of HMX to 64% with the used quantity of HNO3 decreased dramatically.
Wet cyanuric chloride promoted efficient synthesis of amidoalkyl naphthols under solvent-free conditions
Gholam Hossein Mahdavinia , Mohammad A. Bigdeli
2009, 20(4): 383-386  doi: 10.1016/j.cclet.2008.12.018
[Abstract](188) [FullText HTML] [PDF 213KB](0)
An efficient and direct procedure has been developed for the preparation of amidoalkyl naphthols by a one-pot condensation of aryl aldehydes, 2-naphthol and urea or amides, in the presence of wet-cyanuric chloride (wet-TCT) as a catalyst. The reactions were carried out under solvent-free media. The present methodology offers several advantages such as excellent yields, simple procedure and eco-friendly reaction condition.
Synthesis of fused pyran and arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methane in ionic liquid
liquid , Xue Sen Fan , Ying Ying Qu , Xin Ying Zhang , Xia Wang , Jian Ji Wang
2009, 20(4): 387-390  doi: 10.1016/j.cclet.2008.12.021
[Abstract](204) [FullText HTML] [PDF 252KB](1)
Promoted and mediated by an ionic liquid-[bmim][BF4], fused pyrans or arylbis(4-hydroxy-6-methyl-2-oxo-2H-pyran-3-yl)methanes were efficiently and selectively prepared from the reaction of aldehyde and 4-hydroxy-6-methyl-2-oxo-pyran with or without acetic anhydride. By using these novel procedures, pyrimidine nucleoside-fused pyran and arylbis(pyranon-3-yl)methane hybrids with potential biological activities were constructed.
A novel derivative of geldanamycin and its antitumor activity
Liang Li , Hong Liu , Xian Dong Xu , Yong Su Zhen
2009, 20(4): 391-392  doi: 10.1016/j.cclet.2008.11.011
[Abstract](207) [FullText HTML] [PDF 230KB](0)
A new derivative of geldanamycin was synthesized by introducing the 6-cinnamamido-hexyl-amino group into the 17-site of geldanamycin, a heat shock protein 90(Hsp90) inhibitor, to obtain 17-(6-cinnamamido-hexylamino)-17-demethoxygel-danamycin (CNDG). Its in vitro and in vivo antitumor effects were evaluated by MTT assay and xenograft in nude mice.
A mild, simple and efficient method for selective α-monobromination of 1,3-diketones and β-keto-esters using pyridinium bromochromate
Yaghoub Sarrafi , Marzieh Sadatshahabi , Kamal Alimohammadi
2009, 20(4): 393-396  doi: 10.1016/j.cclet.2008.11.022
[Abstract](190) [FullText HTML] [PDF 218KB](0)
Pyridinium bromochromate has been found to be a highly efficient and selective reagent for the α-monobromination of 1,3-diketones and β-keto-esters in the absence of base, Lewis acid, or other catalyst. The products were formed in high to excellent yields under mild reaction conditions and in short reaction times
Rapid and efficient synthesis of new chiral aromatic amide molecular tweezers under solvent-free conditions using microwave
Xiao Xiang Zhao , Zhi Gang Zhao , Xing Li Liu , Xiu Ming Wu
2009, 20(4): 397-400  doi: 10.1016/j.cclet.2008.11.023
[Abstract](199) [FullText HTML] [PDF 225KB](0)
An efficient and simple method for the synthesis of new chiral aromatic amide molecular tweezers by irradiation with microwave under solvent-free conditions has been developed. Its main advantages are short reaction times, good conversions and the environmentally friendly nature of the process.
Microwave-assisted aldol condensation of benzil with ketones
Katayoun Marjani , Maryam Asgari , Akram Ashouri , Gholam Hossein Mahdavinia , Hossien Abbastabar Ahangar
2009, 20(4): 401-403  doi: 10.1016/j.cclet.2008.12.036
[Abstract](208) [FullText HTML] [PDF 208KB](1)
Under microwave irradiation, the corresponding hydroxycyclopentenones were prepared in high yields by the cross-aldol reactions of benzil with various ketones. When the reactions were performed in various solvents under classical heating for a long time, they produced the products in relatively low yields.
Synthesis and antiviral activity of 4H-[1,2,5]oxadiazolo [3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides
Jing Bo Shi , Jing Gao , Ya Ping Wang , Qi Zheng Yao
2009, 20(4): 404-406  doi: 10.1016/j.cclet.2008.12.009
[Abstract](184) [FullText HTML] [PDF 246KB](0)
A series of 4H-[1,2,5]oxadiazolo[3,4-d]pyrimidine-5,7-dione 1-oxide nucleosides was designed, synthesized and evaluated against vesicular stomatitis virus (VSV) inWish cell. The antiviral activities of all compounds were stronger than those of acyclovir,while their toxicities were similar to those of acyclovir.
Highly efficient synthesis of β-amino esters via Mannich-type reaction under solvent-free conditions using ZnCl2 catalyst
Xue Ming Chen , Xing Shu Li , Albert S. C. Chan
2009, 20(4): 407-410  doi: 10.1016/j.cclet.2008.12.030
[Abstract](195) [FullText HTML] [PDF 249KB](0)
β-Amino esters were synthesized via ZnCl2-catalyzed Mannich-type reaction of imines and malonate esters under solvent-free conditions in 6 min. The β-amino ester was converted into the corresponding aspartic acid derivatives.
Study on the synthesis and antimicrobial activity of novel cationic porphyrins
Ke Gui Yu , Dong Hong Li , Cheng He Zhou , Jun Lin Diao
2009, 20(4): 411-414  doi: 10.1016/j.cclet.2008.11.030
[Abstract](255) [FullText HTML] [PDF 362KB](0)
A novel series of quaternary ammonium cationic derivatives based on tetrapyridyl-porphyrin was synthesized. All the compounds were evaluated for their in vitro antibacterial activities against S. aureus, E. coli and P. aeruginosa, and antifungal activities against C. albicans, where microorganisms were exposed and unexposed to the irradiation. The results revealed that some of these compounds, especially, 3a and 4a displayed satisfactory antibacterial activity against Gram-positive bacteria S. aureus and moderate antifungal activity against C. albicans. Unfortunately, Gram-negative bacteria P. aeruginasa was resistant to all compounds. The antimicrobial activity was found to be sensitive to the functional groups attached on the aromatic ring and the complex metal in the porphyrin ring, and decreased with the increase of electron-withdrawing capability of the functional groups. These preliminary results suggested that the remarkable antibacterial efficiency against S. aureus makes these substances promising antimicrobial agents.
Chemoselective N-nitrosation of secondary amines under heterogeneous and mild conditions via in situ generation of HNO2
Arash Ghorbani-Choghamarani , Hamid Goudarziafshar , Somaieh Rezaee , Saiedeh Shima Mortazavi
2009, 20(4): 415-419  doi: 10.1016/j.cclet.2008.12.044
[Abstract](201) [FullText HTML] [PDF 286KB](0)
A wide variety of secondary amines are chemoselectively subjected to N-nitrosation reaction with treatment of citric acid and NaNO2 in the presence of wet SiO2 (50%, w/w) in dichloromethane at room temperatture under heterogeneous conditions. The N-nitrosation method is very simple and products can be easily isolated with good to high yields.
Synthesis and biological evaluation of 2,4-diaminopteridine derivatives as nitric oxide synthase inhibitor
Fei Ma , Gang LÜ , Wei Fen Zhou , Qiu Juan Wang , Yi Hua Zhang , Qi Zheng Yao
2009, 20(4): 420-422  doi: 10.1016/j.cclet.2008.12.012
[Abstract](217) [FullText HTML] [PDF 230KB](0)
A series of novel 2,4-diamino-pteridines (9a-l) were synthesized and evaluated as inhibitors of inducible nitric oxide synthase (iNOS) in vitro. It was found that 9a, 9d, 9e, 9h, 9i and 9l showed potent inhibitory activities similar to that of methotrexate (MTX),while the activities of 9b, 9c, 9f, 9g, 9j and 9k are stronger than MTX.
Yb(OTf)3-catalyzed synthesis of pyrroles under solvent-free conditions
Bing Zuo , Jiu Xi Chen , Miao Chang Liu , Hua Yue Wu , Wei Ke Su
2009, 20(4): 423-426  doi: 10.1016/j.cclet.2008.12.046
[Abstract](191) [FullText HTML] [PDF 263KB](0)
AYb(OTf)3-catalyzed approach for the synthesis of pyrroles under solvent-free conditions was achieved, which could afford the desired products with yields ranged from moderate to excellent.
Novel dihydropyrazole derivatives linked with multi(hetero)aromatic ring: Synthesis and antibacterial activity
Lin Shan Bai , Yan Wang , Xin Hua Liu , Hai Liang Zhu , Bao An Song
2009, 20(4): 427-430  doi: 10.1016/j.cclet.2008.12.013
[Abstract](191) [FullText HTML] [PDF 265KB](0)
Eight novel heterocycle-substituted dihydropyrazole derivatives were synthesized and characterized by ESI-MS, 1H NMR and 13C NMR. All of the compounds have been screened for their antibacterial potential in vitro against Bacillus subtilis,Staphylococcus aureus, Escherichia coli and Pseudomonas aeruginosa. The results show that compounds 9b, 9g and 9h displayed significant activity with MIC values in the range of 0.39-1.562 mg/mL against B. subtilis.
Two novel aconane-type diterpenes derived from C-nor-C19-diterpenoid alkaloid
Xiang Li Shen , Qiao Hong Chen , Dong Lin Chen , Feng Peng Wang
2009, 20(4): 431-434  doi: 10.1016/j.cclet.2008.12.028
[Abstract](187) [FullText HTML] [PDF 299KB](0)
Two novel C-nor-B-homo aconane-type diterpenes 4 and 5, featuring a unique eight-membered ring system, were obtained by the treatment of C-nor-C19-diterpenoid alkaloid 3 with HNO2 in 8% and 21% yields, respectively. Structures of these two compounds were established based on the combination of spectroscopic data, including HRESIMS, 1D and 2D NMR data.A plausible mechanism for the formation of 4 and 5 is also presented.
Synthesis and antibacterial activity of brominated 2'(4')-nitro-3-hydroxy diphenyl ethers
Xue Tang , Min Xie , Yong Xue Sun , Jian Hua Liu , Zhi Cheng Zhong , Yu Liang Wang
2009, 20(4): 435-438  doi: 10.1016/j.cclet.2008.12.027
[Abstract](190) [FullText HTML] [PDF 241KB](0)
Eight new brominated 2'(4')-nitro-3-hydroxy diphenyl ethers have been designed and synthesized. The structures of new compounds were confirmed by 1H NMR, IR and HRMS. The bioactivity tests showed that these compounds possessed antibacterial activities against the tested bacteria. These new compounds cannot be transformed into dioxins when they were manufactured and used.
V(HSO4)3 catalyzed chemoselectivity acetylation of alcohols and phenols in solution and under solvent-free conditions
Farhad Shirini , Ali Reza Sakhaei , Masoumeh Abedini
2009, 20(4): 439-443  doi: 10.1016/j.cclet.2008.11.024
[Abstract](205) [FullText HTML] [PDF 296KB](0)
A variety of alcohols and phenols are efficiently acetylated with acetic anhydride in the presence of a catalytic amount of V(HSO4)3 in solution and under solvent free conditions. Mild reaction conditions, high yields of the products, easy procedure and selective acetylation of alcohols and phenols in the presence of amines and thiols are the main advantages of this procedure.
A new cassane diterpenoid lactone from the seed of Caesalpinia minax
Yan Cheng , Li Yan Maa , Jian Hua Miao , Xu Dong Xu , Jing Quan Yuan , Jun Shan Yang
2009, 20(4): 444-446  doi: 10.1016/j.cclet.2008.12.039
[Abstract](197) [FullText HTML] [PDF 223KB](0)
A new cassane diterpenoid lactone was isolated from the seed of Caesalpinia minax. On the basis of spectral evidences, its structure was established as 12α-methoxyl, 5α, 14β-dihydroxy-1a, 6α, 7β-triacetoxycass-13(15)-en-16, 12-olide.
A new ceramide from transgenic crown galls of Panax quinquefolium
Jian Hua Zhu , Sha Liu , Rong Min Yu
2009, 20(4): 447-449  doi: 10.1016/j.cclet.2008.12.024
[Abstract](186) [FullText HTML] [PDF 209KB](0)
A new ceramide (1) was isolated from transgenic crown galls of Panax quinquefolium. The structure was elucidated as (2S, 3S,4R, 20E)-2-[(2'R)-2'-hydroxyl-palmitoyl-amino]-20-hexacosene-1, 3, 4-triol on the basis of spectroscopic and chemical methods.
A new cytotoxic cardenolide from the latex of Antiaris toxicaria
Yu Juan Gan , Wen Li Mei , You Xing Zhao , Hao Fu Dai
2009, 20(4): 450-452  doi: 10.1016/j.cclet.2008.12.043
[Abstract](182) [FullText HTML] [PDF 222KB](0)
A new cardenolide, toxicarioside E (1), was isolated from the latex of Antiaris toxicaria (Pers.) Lesch (Moraceae). Its structure was elucidated on the basis of spectral data and chemical evidence. Compound 1 showed significant cytotoxicity against K562 and SGC-7901 cell lines in vitro by MTT method with the IC50 value of 0.026 and 0.027μg/mL, respectively.
Two new bromoindoles from red alga Laurencia similis
Hua Su , Zhao Hui Yuan , Jing Li , Shu Ju Guo , Li Ping Deng , Li Jun Han , Xiao Bin Zhu , Da Yong Shi
2009, 20(4): 456-458  doi: 10.1016/j.cclet.2008.12.015
[Abstract](204) [FullText HTML] [PDF 229KB](0)
Two new bromoindole alkaloids have been isolated from the ethanolic extract of the red alga Laurencia similis. On the basis of chemical and spectroscopic methods (including 1D and 2D NMR technique), their structures have been elucidated as 2,2',5,5',6,6'-sixibromo-3, 3'-bi-1H-indole and 3, 5-dibromo-1-methylindole, respectively.
Two new benzophenone glucosides from Cratoxylon cochinchinensis
Hai Yang Yu , San Lin Jin , Xue Zhang , Yuan Liu , Yang Fu Ou , Nai Li Wang , Xin Sheng Yao
2009, 20(4): 459-461  doi: 10.1016/j.cclet.2008.12.038
[Abstract](193) [FullText HTML] [PDF 251KB](1)
Two new benzophenone glucosides were isolated from the 60% ethanol extract of the dried stems of Cratoxylum cochinchinense.The structures were elucidated as 3-O-β-D-glucopyranosyl-2',4,6'-trihydroxy-benzophenone and 3-O-β-D-glucopyranosyl-2',5,6'-trihydroxybenzophenone on the basis of spectral and chemical methods.
Synthesis and characterization of Al doped δ-laminar crystal sodium silicate
Xue Jing Yang , Ya Ling Yang , Wei Zhen , Mou Sheng Liu , Jun Hong Chai
2009, 20(4): 462-464  doi: 10.1016/j.cclet.2008.12.032
[Abstract](190) [FullText HTML] [PDF 1484KB](0)
An modified laminar crystal sodium silicate (Al-SKS-6) was synthesized by spray drying and high temperature crystallization using sodium silicate as silicon source, Al atom as inorganic source and hexadecyltrimethy ammonium bromide (CTMAB) as the structure template. The hydrothermal stability of product was at least 1 h. The synthesized material was characterized by XRD and SEM. The results indicated that shape and intensity of XRD diffraction peak at 2θ took changes, but raw material δ phase crystal form kept unchanged, and assured high Ca2+ and Mg2+ binding capacity of the products. The Ca2+ and Mg2+ binding capacity of product is up to 380 mg Ca/g and 410mg Mg/g respectively. It was found that the hole of product became smaller and appeared rod structure based on SEM. The hydrothermal stability was increased due to the pillaring of Al atom.
Reactions and crystal structures of heterodinuclear complexes R3Sn-M(CO)5 (M=Mn, Re) with some nitrogen ligands
Yong Qiang Ma , Ning Yin , Wen Jing Peng , Jing Li
2009, 20(4): 465-468  doi: 10.1016/j.cclet.2008.12.017
[Abstract](183) [FullText HTML] [PDF 275KB](0)
Some reactions of R3SnM(CO)5 (M=Mn, Re) with CH3CN or pyridine were investigated to give complexes R3SnMn(CO)3LL'or R3SnMn(CO)4L by a facile mild method. X-ray diffractions analyses show that, in contrast to the phosphine ligand occupying in axial position, nitrogen ligands occupy equatorial position.
An enrichment device of silica-based monolithic material and its application to determine micro-carbaryl by NIRS
Yi Ping Du , Xue Mei Wei , Hong Ping Xie , Zi Xia Huang , Juan Juan Fang
2009, 20(4): 469-472  doi: 10.1016/j.cclet.2008.11.017
[Abstract](197) [FullText HTML] [PDF 261KB](0)
Silica-based monolithic column material was synthesized and an enrichment device was fabricated with the material by assembling the material inside a glass column. The enrichment device was applied for the determination of micro-carbaryl with near-infrared spectroscopy (NIRS). The aqueous solutions of carbaryl passed through the device and the carbaryl was enriched on the surface of the material where diffuse reflection NIR spectra were measured. These procedures of enrichment and measurement ensured to concentrate analytes for the measurement, so that the sensitivity of determination of NIRS could be improved. NIR spectra of carbaryl solutions (0.01-1.00μg mL-1), measured after the application of the enrichment device, were pretreated with multiplicative scatter correction (MSC) and regressed against the concentrations of the carbaryl solutions with partial least squares (PLS) method. The results showed that the minimum value of root-mean-square error of prediction (RMSEP) was 0.1771μg mL-1 when the number of latent variables was 3 of PLS regression. Therefore, the number of latent variables 3 was selected as the optimum value. RMSEP was not very low but acceptable considering that NIRS is commonly used in macro amount analysis and it is quite difficult for NIRS to determine micro amount analytes, especially, less than 1μg mL-1.
pH-sensitive polymer-assisted refolding of urea-denatured fibroblast growth factor
Zhi Feng Huang , Shan Shan Wang , Chun Yan Ni , Shu Lin Yang , Xiao Kun Li , Susanna S. J. Leong
2009, 20(4): 473-477  doi: 10.1016/j.cclet.2008.12.014
[Abstract](213) [FullText HTML] [PDF 671KB](0)
A pH-responsive polymer Eudragit S-100 has been found to assist in correct folding of FGF-2(fibroblast growth factor-2) denatured with 8 mol/L urea and 10 mmol/L dithiothreitol at pH 7.2. The refolding of FGF-2 was performed by directly diluting denatured FGF-2 into a refolding buffer containing Eudragit S-100. The ability of Eudragit S-100 to enhance protein refolding level was investigated using MTT method, fluorescence emission spectroscopy and reverse phase HPLC. On the other hand, the result shows the ability of Eudragit S-100 to enhance the refolding level of protein is due to the interaction between Eudragit S-100 and positively charged FGF-2.
Monomer reactivity ratios for fluoroacrylate and butyl methacrylate in miniemulsion copolymerizations initiated by potassium persulphate
Qing Hua Zhang , Zhen Huan Luo , Xiao Li Zhan , Feng Qiu Chen
2009, 20(4): 478-482  doi: 10.1016/j.cclet.2008.12.041
[Abstract](232) [FullText HTML] [PDF 348KB](0)
Miniemulsion copolymerization of butyl mathacrylate (BMA) with fluoroacrylate (HFMA, TFMA) was carried out at 70℃ by employing potassium persulphate (KPS) as initiator. Copolymer compositions at low conversion levels were determined by 1H NMR spectra techniques. The reactivity ratios were evaluated by employing Kellen-Tudos (K-T) methods, which yields the apparent reactivity ratios, rBMA=0.74, rHFMA=0.87 and rBMA=0.73, rTFMA=0.75, respectively, and Q-and e-values of HFMA and TFMAwere calculated by the Alfrey-Price method. The results show that HFMA and TFMA are more active than BMA, and the cross-propagation rate constant is greater than the self-propagation one in these two copolymerizations.
Synthesis and characterization of novel polypropylene paper releasing anion
Li Qiu Wang , Qing Shan Li , Hui Peng Ma , Xiao Feng Guo , Rui Hong Wang , Gang Yao
2009, 20(4): 483-486  doi: 10.1016/j.cclet.2008.12.034
[Abstract](211) [FullText HTML] [PDF 1511KB](0)
Polypropylene synthetic paper releasing anion was prepared from polypropylene resin, anion additives, titanium dioxide, etc., by calendar forming method. The synthetic paper was tested by anion detector, SEM, AFM, etc. Tensile strength, elongation at break,right angle tear strength of the polypropylene synthetic paper reached the GB 13022 or QB/T1130 Standard. The synthetic paper was water and oil resistance, and released anions 10,530 cm-3. It was environment-friendly, and a kind of good material for human's health.
Thermal degradation and isothermal crystalline behavior of poly(trimethylene terephthalate)
Jian Liu , Shu Guang Bian , Min Xiao , Shuan Jin Wang , Yue Zhong Meng
2009, 20(4): 487-491  doi: 10.1016/j.cclet.2008.11.035
[Abstract](204) [FullText HTML] [PDF 461KB](0)
Poly(trimethylene terephthalate) (PTT) is an excellent fiber material. Its thermal degradation and isothermal crystalline behaviors were in this study investigated using thermogravimetric analysis (TGA), thermogravimetric analysis-Fourier transform infrared spectroscopy (TGA-FTIR) analysis, differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The thermal degradation mechanism of PTT follows Mclafferty rearrangement principle. The PTTwith intrinsic viscosity (IV) of 0.74 dl/g has a maximum crystallinity of about 55% at 190℃, as demonstrated by DSC and XRD measurements consistently.
Synthesis and application of a hydrophobic hypercrosslinked polymeric resin for removing VOCs from humid gas stream
Peng Liu , Chao Long , Hong Ming Qian , Ying Li , Ai Min Li , Quan Xing Zhang
2009, 20(4): 492-495  doi: 10.1016/j.cclet.2008.11.019
[Abstract](197) [FullText HTML] [PDF 270KB](0)
A hydrophobic hypercrosslinked polymeric resin LC-1 was prepared and characterized. The properties of LC-1 resin were compared with those of a commercial hypercrosslinked polymer NDA-201 resin. In addition, the dynamic adsorption of trichloroethylene (TCE) onto LC-1 under dry and humid conditions at 303 K was investigated, the result shows that LC-1 possesses high hydrophobic property and can remove TCE from gas stream without effect of high humidity efficiently.
Development and characterization of new polyclonal antibodies specific for three polychlorinated biphenyls
Han Yu Chen , Hui Sheng Zhuang , Chun Zhou
2009, 20(4): 496-500  doi: 10.1016/j.cclet.2008.12.022
[Abstract](205) [FullText HTML] [PDF 277KB](0)
Three polychlorinated biphenyls (PCBs) congeners and their corresponding haptens bearing four carbon length carboxylic groups that can be linked to a protein for raising antibodies were synthesized. The three resultant immunogens were fabricated and used to stimulate immune responses in rabbits to survey the characteristics of the haptens. Three of the resultant polyclonal antibodies (Pabs) were obtained. The antiserum exhibited relatively high antibody titres (1:32-64) in double agar diffusion.
Evaluation of attraction terms in equations of state on the prediction of solubility of some biomolecules in supercritical carbon dioxide
Mohammad Reza Bozorgmehr , Mohammad Reza Housaindokht
2009, 20(4): 501-505  doi: 10.1016/j.cclet.2008.12.020
[Abstract](197) [FullText HTML] [PDF 260KB](0)
In the present work, effect of the attraction terms of four recently modified Peng-Robinson equations of state on the prediction of solubility of caffeine, cholesterol, uracil and erythromycin was studied. The attraction terms of two of these equations are linear relative to the acentric factor and for the other two are exponential. It is found that the later show less deviation. Also interaction parameters for the studied systems are obtained and the percentage of average absolute relative deviation (%AARD) in each calculation is displayed.
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