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Lux DM, Aryal V, Niroula D, Giri R. Nickel-Catalyzed Regioselective Intermolecular Dialkylation of Alkenylarenes: Generation of Two Vicinal C(sp 3 )-C(sp 3 ) Bonds Across Alkenes. Angew Chem Int Ed Engl 2023; 62:e202305522. [PMID: 37316459 PMCID: PMC10528944 DOI: 10.1002/anie.202305522] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 05/22/2023] [Accepted: 06/14/2023] [Indexed: 06/16/2023]
Abstract
We disclose a Ni-catalyzed regioselective dialkylation reaction of alkenylarenes with α-halocarbonyls and alkylzinc reagents. The reaction produces γ-arylated alkanecarbonyl compounds with the generation of two new C(sp3 )-C(sp3 ) bonds at the vicinal carbons of alkenes. This reaction is effective for the use of primary, secondary and tertiary α-halocarboxylic esters, amides and ketones in conjunction with primary and secondary alkylzinc reagents as the sources of two C(sp3 ) carbons for the dialkylation of terminal and cyclic internal alkenes.
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Affiliation(s)
| | | | | | - Ramesh Giri
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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2
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Sapkota RR, Tak RK, Aryal V, Niroula D, Secosky NC, Dhungana RK, Giri R. Cu-Catalyzed Cyclization/Coupling of Alkenyl Aldimines with Arylzinc Reagents: Access to Indole-3-diarylmethanes. Org Lett 2022; 24:6213-6218. [PMID: 35969494 DOI: 10.1021/acs.orglett.2c02531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
We report a Cu(II)-catalyzed cyclization/coupling of alkenyl aldimines with arylzinc reagents to create indole-3-diarylmethane derivatives (Sapkota et al. ChemRxiv 2022, DOI: 10.26434/chemrxiv-2022-d6qn). The current reaction provides a unified modular route from readily available starting materials to indole-3-diarylmethanes in which all three arene cores can be decorated with differential functional substitutions on demand. Since the cyclization/coupling of alkenyl aldimines is unknown to date, the current method widens the scope with regard to both the substrate and product diversity for this class of reaction.
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Affiliation(s)
- Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Raj Kumar Tak
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Vivek Aryal
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Doleshwar Niroula
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Nicholas C Secosky
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Roshan K Dhungana
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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3
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Aryal V, Chesley LJ, Niroula D, Sapkota RR, Dhungana RK, Giri R. Ni-Catalyzed Regio- and Stereoselective Alkylarylation of Unactivated Alkenes in γ,δ-Alkenylketimines. ACS Catal 2022; 12:7262-7268. [PMID: 37829145 PMCID: PMC10569404 DOI: 10.1021/acscatal.2c01697] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
We disclose a Ni-catalyzed vicinal alkylarylation of unactivated alkenes in γ,δ-alkenylketimines with aryl halides and alkylzinc reagents. The reaction produces γ-C(sp3)-branched δ-arylketones with the construction of two new C(sp3)-C(sp3) and C(sp3)-C(sp2) bonds. Electron-deficient alkenes play crucial dual roles as ligands to stabilize reaction intermediates and to increase catalytic rates for the formation of C(sp3)-C(sp3) bonds. This alkene alkylarylation reaction is also effective for secondary alkylzinc reagents and internal alkenes, and proceeds with a complete regio- and stereocontrol, affording products with up to three contiguous all-carbon all-cis secondary stereocenters.
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Affiliation(s)
- Vivek Aryal
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Lucas J Chesley
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Doleshwar Niroula
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Roshan K Dhungana
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802
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4
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Dhungana RK, Sapkota RR, Wickham LM, Niroula D, Shrestha B, Giri R. Ni‐Catalyzed Arylbenzylation of Alkenylarenes: Kinetic Studies Reveal Autocatalysis by ZnX
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**. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202110459] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Affiliation(s)
- Roshan K. Dhungana
- Department of Chemistry Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Rishi R. Sapkota
- Department of Chemistry Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Laura M. Wickham
- Department of Chemistry Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Doleshwar Niroula
- Department of Chemistry Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Bijay Shrestha
- Current address: Department of Chemistry and Biochemistry University of California Los Angeles CA 90095 USA
| | - Ramesh Giri
- Department of Chemistry Pennsylvania State University University Park Pennsylvania 16802 USA
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Dhungana RK, Sapkota RR, Wickham LM, Niroula D, Shrestha B, Giri R. Ni-Catalyzed Arylbenzylation of Alkenylarenes: Kinetic Studies Reveal Autocatalysis by ZnX 2 *. Angew Chem Int Ed Engl 2021; 60:22977-22982. [PMID: 34427992 PMCID: PMC8490319 DOI: 10.1002/anie.202110459] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Indexed: 11/08/2022]
Abstract
We report a Ni-catalyzed regioselective arylbenzylation of alkenylarenes with benzyl halides and arylzinc reagents. The reaction furnishes differently substituted 1,1,3-triarylpropyl structures that are reminiscent of the cores of oligoresveratrol natural products. The reaction is also compatible for the coupling of internal alkenes, secondary benzyl halides and variously substituted arylzinc reagents. Kinetic studies reveal that the reaction proceeds with a rate-limiting single-electron-transfer process and is autocatalyzed by in-situ-generated ZnX2 . The reaction rate is amplified by a factor of three through autocatalysis upon addition of ZnX2 .
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Affiliation(s)
| | | | | | | | | | - Ramesh Giri
- Department of Chemistry Pennsylvania State University, University Park, Pennsylvania 16802, USA
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6
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Dhungana RK, Aryal V, Niroula D, Sapkota RR, Lakomy MG, Giri R. Nickel‐Catalyzed Regioselective Alkenylarylation of γ,δ‐Alkenyl Ketones via Carbonyl Coordination. Angew Chem Int Ed Engl 2021. [DOI: 10.1002/ange.202104871] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Affiliation(s)
- Roshan K. Dhungana
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
| | - Vivek Aryal
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
| | - Doleshwar Niroula
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
| | - Rishi R. Sapkota
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
| | - Margaret G. Lakomy
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
| | - Ramesh Giri
- Department of Chemistry Pennsylvania State University University Park PA 16802 USA
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7
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Dhungana RK, Aryal V, Niroula D, Sapkota RR, Lakomy MG, Giri R. Nickel-Catalyzed Regioselective Alkenylarylation of γ,δ-Alkenyl Ketones via Carbonyl Coordination. Angew Chem Int Ed Engl 2021; 60:19092-19096. [PMID: 34115911 PMCID: PMC8373804 DOI: 10.1002/anie.202104871] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/08/2021] [Revised: 05/27/2021] [Indexed: 11/07/2022]
Abstract
We disclose a nickel-catalyzed reaction, which enabled us to difunctionalize unactivated γ,δ-alkenes in ketones with alkenyl triflates and arylboronic esters. The reaction was made feasible by the use of 5-chloro-8-hydroxyquinoline as a ligand along with NiBr2 ⋅DME as a catalyst and LiOtBu as base. The reaction proceeded with a wide range of cyclic, acyclic, endocyclic and exocyclic alkenyl ketones, and electron-rich and electron-deficient arylboronate esters. The reaction also worked with both cyclic and acyclic alkenyl triflates. Control experiments indicate that carbonyl coordination is required for the reaction to proceed.
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Affiliation(s)
- Roshan K. Dhungana
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Vivek Aryal
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Doleshwar Niroula
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Rishi R. Sapkota
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Margaret G. Lakomy
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
| | - Ramesh Giri
- Department of Chemistry, Pennsylvania State University, University Park, Pennsylvania 16802, USA
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Dhungana RK, Sapkota RR, Wickham LM, Niroula D, Giri R. Correction to "Ni-Catalyzed Regioselective 1,2-Dialkylation of Alkenes Enabled by the Formation of Two C(sp 3)-C(sp 3) Bonds". J Am Chem Soc 2021; 143:10805. [PMID: 34251795 DOI: 10.1021/jacs.1c06574] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Dhungana RK, Sapkota RR, Wickham LM, Niroula D, Giri R. Ni-Catalyzed Regioselective 1,2-Dialkylation of Alkenes Enabled by the Formation of Two C(sp 3)-C(sp 3) Bonds. J Am Chem Soc 2020; 142:20930-20936. [PMID: 33271014 PMCID: PMC7953840 DOI: 10.1021/jacs.0c09778] [Citation(s) in RCA: 27] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
Abstract
We disclose a Ni-catalyzed vicinal difunctionalization of alkenes with benzyl halides and alkylzinc reagents, which produces products with two new alkyl-alkyl bonds. This alkene dialkylation is effective in combining secondary benzyl halides and secondary alkylzinc reagents with internal alkenes, which furnishes products with three contiguous all-carbon secondary stereocenters. The products can be readily elaborated to access complex tetralene, benzosuberene, and bicyclodecene cores. The reaction also features as the most efficient alkene difunctionalization process to date with catalyst loadings down to 500 ppm and the catalytic turnover number (TON) and turnover frequency (TOF) registering up to 2 × 103 and 165 h-1 at rt, respectively.
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Affiliation(s)
- Roshan K Dhungana
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Laura M Wickham
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Doleshwar Niroula
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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10
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Dhungana RK, Sapkota RR, Niroula D, Giri R. Walking metals: catalytic difunctionalization of alkenes at nonclassical sites. Chem Sci 2020; 11:9757-9774. [PMID: 34094239 PMCID: PMC8162390 DOI: 10.1039/d0sc03634j] [Citation(s) in RCA: 69] [Impact Index Per Article: 17.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2020] [Accepted: 09/06/2020] [Indexed: 12/25/2022] Open
Abstract
Migration of metals along a carbon chain is triggered by two of the most common organometallic elementary steps - β-hydride (β-H) elimination and alkene hydrometallation. This process heralds a new future for creating bonds at carbon sites that fall outside the tenets of the conventional wisdom for reactivity and bond formation, and provides an opportunity to leverage β-H elimination to advance the very reaction of alkene difunctionalization it is intrinsically predestined to disrupt. Almost four decades since its genesis, the early adventure for alkene difunctionalization by metal migration was sporadic, and its later development went on a hiatus primarily due to original impetus on arresting β-H elimination for vicinal alkene difunctionalization. With the recent surge on alkene difunctionalization, efforts have been gradually shifting to harnessing the process of β-H elimination to difunctionalize alkenes at sites other than the classical vicinal carbons, termed henceforth nonclassical reaction sites for pedagogical simplicity. In this review article, we extricate and examine the origin and the development of such reactions over the years. This review covers a wide range of reactions for the difunctionalization of alkenes at geminal (1,1), allylic (1,3) and remote (1,n) carbon sites with a variety of coupling partners. These reactions have enabled engineering of complex molecular frameworks with the generation of new carbon-carbon (C-C)/C-C, C-C/C-heteroatom (halogens, O, N, B) and C-B/C-B bonds. The development of these unique transformations is also presented with mechanistic hypotheses and experimental evidences put forward by researchers. Judged by the number of reports emerging recently, it is now strikingly evident that the field of alkene difunctionalization by metal migration has begun to gain momentum, which holds a great future prospect to develop into a synthetic method of enormous potential.
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Affiliation(s)
- Roshan K Dhungana
- Department of Chemistry, The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Doleshwar Niroula
- Department of Chemistry, The Pennsylvania State University University Park Pennsylvania 16802 USA
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University University Park Pennsylvania 16802 USA
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11
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Niroula D, Sapkota RR, Dhungana RK, Shrestha B, Giri R. An Expedient Route to 9-arylmethylanthracene Derivatives via Tandem Ni-catalyzed Alkene Dicarbofunctionalization and Acid-promoted Cyclization-aromatization. Isr J Chem 2020; 60:424-428. [PMID: 34045772 PMCID: PMC8153705 DOI: 10.1002/ijch.201900158] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2019] [Accepted: 01/21/2020] [Indexed: 12/15/2022]
Abstract
We report a nickel-catalyzed one pot synthesis of 9-arylmethylanthracene motifs, which find applications in medicinal and material chemistry. In this synthesis, we apply three component alkene dicarbofunctionalization of 2-vinylaldimines with aryl iodides and arylzinc reagent to generate a 1,1,2-diarylethyl scaffold, which then undergoes an acidpromoted cyclization followed by aromatization to furnish 9-arylmethylanthracene cores. With the new method, a number of differently-substituted 9-arylmethylanthracene derivatives can be synthesized in good yields.
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Affiliation(s)
- Doleshwar Niroula
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Rishi R Sapkota
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Roshan K Dhungana
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
| | - Bijay Shrestha
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
- Department of Chemistry, University of Illinois, 600 South, Mathews Avenue, Urbana, Illinois 61801, United States
| | - Ramesh Giri
- Department of Chemistry, The Pennsylvania State University, University Park, Pennsylvania 16802, United States
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12
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Regmee P, Rimal J, Maharjan IK, Shrestha A, Niroula D, Luitel A, Chaudhary SK. Microinvasion: A Clinical Dilemma. Kathmandu Univ Med J (KUMJ) 2019; 17:70-72. [PMID: 31734683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Microinvasive oral squamous cell carcinoma (MIOSCC) is an early stage malignant tumour,showing invasion of the epithelial cells confined to the superficial lamina propria. This is matter of debate in respect to the clinical presentation, metastasis, therapeutic intervention and prognosis. A 32-year female reported to the department with chief complaint of wound and burning sensation in her left back region of lower gums. Clinical diagnosis of erosive oral lichen planus was made and topical steroid was started. The lesion clinically healed with the use of topical medicine. After stopping the medication the lesion recurred, following which, excisional biopsy was done. On histopathological evaluation diagnosis of microinvasive oral squamous cell carcinoma was made. Recurrence of similar symptom in the same site was seen 10 weeks later, which now showed features of moderate dysplasia. Clinical features of microinvasive oral squamous cell carcinoma resembles premalignant lesion, leading to difficulty in diagnosis, treatment and prognostic assessment. Thus, adequate representation of this entity is necessary.
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Affiliation(s)
- P Regmee
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - J Rimal
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - I K Maharjan
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - A Shrestha
- Department of Oral Pathology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - D Niroula
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - A Luitel
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
| | - S K Chaudhary
- Department of Periodontology and Oral Implantology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Nepal
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Abstract
A total synthesis of the cytotoxic terpenoid hortonone C was accomplished and its absolute stereochemistry confirmed. Intermediate (+)-4 was synthesized using either an asymmetric conjugate addition strategy, or by elaboration of the Hajos-Parrish ketone. Reduction of (+)-4 under dissolving-metal conditions and trapping the enolate intermediate served to control the cis-stereochemistry at the ring fusion and provide a silyl enol ether necessary for ring expansion. Comparison of optical rotation data confirmed that the absolute configuration of natural hortonone C is (6S,7S,10S).
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Affiliation(s)
- Doleshwar Niroula
- Department of Chemistry, New Mexico Institute of Mining and Technology, Socorro NM 87801, United States
| | - Liam P Hallada
- Department of Chemistry, New Mexico Institute of Mining and Technology, Socorro NM 87801, United States; Department of Biology, New Mexico Institute of Mining and Technology, Socorro NM 87801, United States
| | - Snezna Rogelj
- Department of Biology, New Mexico Institute of Mining and Technology, Socorro NM 87801, United States
| | - Rodolfo Tello-Aburto
- Department of Chemistry, New Mexico Institute of Mining and Technology, Socorro NM 87801, United States
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14
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Luitel A, Rimal J, Maharjan IK, Niroula D, Regmee P. Even a Tooth Slips Sometimes. Kathmandu Univ Med J (KUMJ) 2016; 14:285-287. [PMID: 28814696] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/07/2023]
Abstract
While impaction of a tooth or two in dentoalveolar region is common, ectopic presence of them in non-dentate area is less commonly reported. A 45-year-old female reported to the department with pain on right back teeth region since two days. On examination, grossly decayed 46, root stump 47, missing 48, with poor periodontal status were noted. Panoramic radiograph was advised for screening, which revealed an inverted impacted 48 at the right ramus just below subcondylar region. However, it was an incidental finding and the patient was asymptomatic, she was informed about the pros and the cons of her case and kept under close monitoring.
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Affiliation(s)
- A Luitel
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal
| | - J Rimal
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal
| | - I K Maharjan
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal
| | - D Niroula
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal
| | - P Regmee
- Department of Oral Medicine and Radiology, College of Dental Surgery, BP Koirala Institute of Health Sciences, Dharan, Sunsari, Nepal
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Tello-Aburto R, Hallada LP, Niroula D, Rogelj S. Total synthesis and absolute stereochemistry of the proteasome inhibitors cystargolides A and B. Org Biomol Chem 2015; 13:10127-30. [PMID: 26400369 DOI: 10.1039/c5ob01821h] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The absolute stereochemistry of the cystargolides was determined by total synthesis. Evaluation of synthetic cystargolides and derivatives showed that the natural (2S,3R) stereochemistry is essential for activity. Moreover, benzyl esters (-)-10 and (-)-15 were found to be about 100 times more potent, and to selectively kill MCF-7 cancerous cells.
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Affiliation(s)
- Rodolfo Tello-Aburto
- Department of Chemistry, New Mexico Institute of Mining and Technology, Socorro, NM 87801, USA.
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