Padinjare Veetil Saranya , Rose Mary Philip , Gopinathan Anilkumar
{"title":"Synthesis of imidazo[1,2-a]pyridines via cobalt/iodine-catalyzed Ortoleva-King type approach","authors":"Padinjare Veetil Saranya , Rose Mary Philip , Gopinathan Anilkumar","doi":"10.1016/j.tetlet.2024.155188","DOIUrl":"10.1016/j.tetlet.2024.155188","url":null,"abstract":"<div><p>Ortoleva-King type reaction of 2-aminopyridines with easily available aromatic ketones by dual catalytic system of cobalt and iodine in chlorobenzene was proposed. The reaction made use of the <em>in situ</em> formation of α-halo ketones from aromatic ketones and molecular iodine. An array of functional groups were tolerated in this strategy to allow the synthesis of variously substituted imidazo[1,2-<em>a</em>]pyridines in moderate to good yields. Furthermore, this procedure was effectively used for the synthesis of zolimidine, a medicine that is sold as an anti-ulcer agent.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141850352","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Efficient synthesis of (±)-de-O-methyllasiodiplodin","authors":"Jesus M. Madrigal Lombera, Ian B. Seiple","doi":"10.1016/j.tetlet.2024.155184","DOIUrl":"10.1016/j.tetlet.2024.155184","url":null,"abstract":"<div><p>Resorcinolic macrolides are a large class of fungal natural products with conserved resorcinolic ester cores within highly variable ten- to fourteen-membered macrocycles. They exhibit a broad range of biological activities, depending largely on the size and substitution on the macrocycle bridge. Here, we report a protecting group-free synthesis of <span><math><mrow><mo>(</mo><mo>±</mo><mo>)</mo></mrow></math></span>-de-<em>O</em>-methyllasiodiplodin, a minimal resorcinolic macrolide derived from the fungus <em>Lasiodiplodia theobromae</em>. The route proceeds in 42% yield over 5 steps (longest linear sequence) from 9-decenoic acid, a cheap and abundant starting material. Given the broad commercial availability of a variety of similar (terminal)-enoic acids, this route provides an entry to libraries of resorcinolic macrolides with highly variable macrocycle bridges.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-18","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141844482","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"A sustainable approach to microwave assisted synthesis of 2-(het)/arylquinazolin-4(3H)-ones via ionic liquid supported Cu(II) catalyst","authors":"Md Gulzar Ahmad , Balamurali MM , Kaushik Chanda","doi":"10.1016/j.tetlet.2024.155182","DOIUrl":"10.1016/j.tetlet.2024.155182","url":null,"abstract":"<div><p>An efficient and sustainable approach for the microwave assisted synthesis of 2-(het)/arylquinazolin-4(3H)-ones from substituted 2-aminobenzamide and benzyl alcohols is introduced by using a reusable imidazolium based ionic liquid supported Cu(II) catalyst. This methodology exhibits high functional group tolerance and efficiently constructs desired products in good to excellent yields. Moreover, this method portrays operational simplicity, less reaction time, minimal cost and sustainable over the reported protocols. Furthermore, the catalyst can be recycled and reused up to 4 consecutive cycles with no significant loss of activity.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141716534","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Structures of bicyclic hexapeptides RA-XXVII and RA-XXVIII from Rubia cordifolia L.","authors":"Haruhiko Fukaya , Tatsuro Anzai , Tomoyo Hasuda , Koichi Takeya , Yutaka Aoyagi , Takahisa Nakane , Yukio Hitotsuyanagi","doi":"10.1016/j.tetlet.2024.155190","DOIUrl":"10.1016/j.tetlet.2024.155190","url":null,"abstract":"<div><p>Two bicyclic hexapeptides RA-XXVII and RA-XXVIII, featuring a phenylpropanoid unit attached to the aromatic ring of the Tyr-6 residue of deoxybouvardin, were isolated from the roots of <em>Rubia cordifolia</em> L. Their structures were determined on the basis of spectroscopic data and X-ray crystallography of the 4-<em>O</em>-methyl derivative of RA-XXVII, and the semisynthesis from deoxybouvardin and coniferyl alcohol. RA-XXVII and RA-XXVIII exhibited cytotoxic activity with IC<sub>50</sub> values of 0.051 and 0.18 μM, respectively, against the HL-60 cell line, and 0.18 and 0.78 μM, respectively, against the HCT-116 cell line.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-15","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141692099","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Riley R. Hughes, Lorenzo D. Battistoni, Matthew J. Ciesla, Te’jandrio Bolton, Patrick M. Asher, Giancarlo Irizarry, Alma de Jesus Antonio Martinez, Kristen M. Baker, Seann P. Mulcahy
{"title":"Asymmetric synthesis of an atropisomeric β-carboline via regioselective intermolecular Rh(I)-catalyzed [2 + 2 + 2] cyclotrimerization","authors":"Riley R. Hughes, Lorenzo D. Battistoni, Matthew J. Ciesla, Te’jandrio Bolton, Patrick M. Asher, Giancarlo Irizarry, Alma de Jesus Antonio Martinez, Kristen M. Baker, Seann P. Mulcahy","doi":"10.1016/j.tetlet.2024.155187","DOIUrl":"10.1016/j.tetlet.2024.155187","url":null,"abstract":"<div><p>The rational design of atropisomeric small molecules is becoming increasingly common in chemical synthesis as a result of the unique advantages this property provides in drug discovery, asymmetric catalysis, and chiroptical activity. In this study, we designed a synthesis of a configurationally stable β-carboline in six steps. Our synthesis made use of an innovative Grignard addition/elimination reaction that formed an yne-ynamide precursor that then reacted with ethyl cyanoformate in a rhodium(I)-catalyzed [2 + 2 + 2] cyclotrimerization reaction to give the atropisomeric β-carboline in excellent yield, good enantioselectivity, and excellent regioselectivity. Extensive optimization of this transformation is described. Racemization kinetics experiments were also conducted on the individual atropisomers and their absolute configurations were determined by circular dichroism.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-14","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141638025","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Jie Wang , Yao-Dong Li , Ye Ge , Xue-Rui Gao , Lin-Hu Li , Hua-Jin Xu , Yi Hu
{"title":"A concise and mild condition for Pd-catalyzed C(sp2)–H arylation","authors":"Jie Wang , Yao-Dong Li , Ye Ge , Xue-Rui Gao , Lin-Hu Li , Hua-Jin Xu , Yi Hu","doi":"10.1016/j.tetlet.2024.155195","DOIUrl":"10.1016/j.tetlet.2024.155195","url":null,"abstract":"<div><p>It is particularly significant to develop mild and efficient methods to construct 2-aryl-substituted benzoic acids framwork due to their wide existence in many important natural organic compounds. Here, we report a concise and mild method to synthesize <em>ortho</em>-arylation of benzoic acids. In this mild catalytic system, decarboxylation byproducts were not observed. Meanwhile, the high yields could be obtained in the absence of ligands.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141622828","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Ranjit S. Karche , Shubham R. Bankar , Vrushali H. Jadhav
{"title":"Alternative synthetic route for the pharmacophore of anticancer agent: Triazolopyridazine derivative","authors":"Ranjit S. Karche , Shubham R. Bankar , Vrushali H. Jadhav","doi":"10.1016/j.tetlet.2024.155193","DOIUrl":"10.1016/j.tetlet.2024.155193","url":null,"abstract":"<div><p>ATAD2 has received attention as one of the potential oncogene with tumor-promoting aspects in many malignancies. ATAD2 is a highly conserved bromodomain family protein that exerts its biological functions by mainly AAA ATPase and bromodomain. Several small molecule inhibitors have been described in the literature. AZ13824374 (<strong>1)</strong> recently reported by Holt and co-workers showed promising in vitro (bio-chemical, cellular) and antiproliferative activity in range of breast cancer models. In this work, we described scalable synthetic route for triazolopyridazine derivative (<strong>2)</strong>, a key intermediate of AZ13824374 (<strong>1)</strong> without using CO in the process. Triazolopyridazine helps to attain the bioactive conformation for AZ13824374 (<strong>1)</strong> through its crucial interaction with Tyr 1021 of ATAD2. Additionally, triazolopyridazine is extensively used as an intermediate for anticancer agents. This encouraged us to develop cost-effective and scalable process for it.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-11","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141638024","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Baozhen Yang, Longkang Yang, Chengrong Lu, Bei Zhao, Yizhe Huang
{"title":"Enantioselective Michael addition of malonates to α,β-unsaturated ketones catalyzed by rare-earth metal amides RE[N(SiMe3)2]3 with phenoxy-functionalized amino alcohol proligands","authors":"Baozhen Yang, Longkang Yang, Chengrong Lu, Bei Zhao, Yizhe Huang","doi":"10.1016/j.tetlet.2024.155175","DOIUrl":"https://doi.org/10.1016/j.tetlet.2024.155175","url":null,"abstract":"<div><p>A combination of rare-earth metal amides RE[<em>N</em>(<em>SiMe</em><sub>3</sub>)<sub>2</sub>]<sub>3</sub> and chiral phenoxy-functionalized amino alcohol proligands was developed to realize the enantioselective Michael addition of malonates with unsaturated ketones. The reactions catalyzed by samarium amide Sm[<em>N</em>(<em>SiMe</em><sub>3</sub>)<sub>2</sub>]<sub>3</sub> were performed best together with the chiral proligand H<sub>3</sub>L<sup>1</sup> (H<sub>3</sub>L<sup>1</sup> = 2,4-di-<em>tert</em>-butyl-6-((((1<em>S</em>,2<em>R</em>)-2-hydroxy-1,2-diphenylethyl) amino)methyl)phenol) in DCE with good group tolerance, mostly in high to excellent yields (85–98 %) and good to excellent ee values (50− >99 %). The possible mechanism was also proposed.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-10","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141595946","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Total synthesis of nepodin and torachrysone glucosides: Evidence for naturally occurring l-glucosides","authors":"Mizuki Makita, Ken-ichi Nihei","doi":"10.1016/j.tetlet.2024.155191","DOIUrl":"10.1016/j.tetlet.2024.155191","url":null,"abstract":"<div><p>The first concise synthesis of nepodin-1-<em>O</em>-<em>β</em>-<span>d</span>-glucopyranoside (D-<strong>1</strong>) and its <span>l</span>-glucopyranoside (L-<strong>1</strong>), as well as torachrysone-1-<em>O</em>-<em>β</em>-<span>d</span>-glucopyranoside (D-<strong>2</strong>) and its <span>l</span>-glucopyranoside (L-<strong>2</strong>), was achieved <em>via</em> Fries rearrangement and selective glycosylation. Spectral data, particularly the specific rotation signs of the synthetic <span>l</span>-glucosides, correlated with those of natural products previously isolated from <em>Rumex dentatus</em>. This confirms the presence of naturally occurring <span>l</span>-glucosides, L-<strong>1</strong> and L-<strong>2</strong>, identified through synthetic approaches.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.sciencedirect.com/science/article/pii/S0040403924002867/pdfft?md5=fcac831db7f019422a172dd0db77982b&pid=1-s2.0-S0040403924002867-main.pdf","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141707192","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"1,2,3-Triazole – [1,2,4]triazolo[3,4-b][1,3,4]thiadiazine hybrids: A switch for improvement of antibreast cancer activity targeting epidermal growth factor receptor","authors":"Praveen Telukuntla , Munugala Chandrakanth , P.G. Amrutha , Neethu Mariam Thomas , Ramesh Gondru , Krishna Reddy Valluru , Janardhan Banothu","doi":"10.1016/j.tetlet.2024.155180","DOIUrl":"https://doi.org/10.1016/j.tetlet.2024.155180","url":null,"abstract":"<div><p>The development of anticancer agents targeting EGFR represents a promising strategy in the field of medicinal chemistry. Consequently, a novel series of 1,2,3-triazole – [1,2,4]triazolo[3,4-<em>b</em>][1,3,4]thiadiazine hybrids (<strong>7a-i</strong> & <strong>8a-f</strong>) were designed, synthesized, and screened for their <em>in vitro</em> anticancer activity against three human breast cancer cell lines, MCF-7, MDA-MB-231, and MDA-MB-415. Notably, hybrids <strong>7f</strong> and <strong>7h</strong>, featuring 4-fluorophenyl and 3,5-dichlorophenyl substitutions, respectively, exhibited superior activity against MCF-7 and MDA-MB-231 cell lines, and comparable activity against MDA-MB-415 cell line, compared to the standard drug Erlotinib. Toxicity studies on the noncancerous breast cell line MCF-10A indicate that these compounds are selective for cancer cell lines. Furthermore, these compounds demonstrated high efficacy in the <em>in vitro</em> EGFR inhibition assay, with IC<sub>50</sub> values of 0.419 ± 0.05 μM and 0.312 ± 0.02 μM, respectively, in comparison to Erlotinib (IC<sub>50</sub>: 0.421 ± 0.03 μM). <em>In silico</em> experiments, including molecular docking studies to elucidate the interaction mode with the EGFR active site and ADMET analysis to verify drug-likeness properties, were also conducted for the potent compounds. Both experimental and <em>in silico</em> investigations suggest that compounds <strong>7f</strong> and <strong>7h</strong> hold promise as lead compounds for further drug design and development endeavors.</p></div>","PeriodicalId":438,"journal":{"name":"Tetrahedron Letters","volume":null,"pages":null},"PeriodicalIF":1.5,"publicationDate":"2024-07-09","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"141607576","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":4,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}