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Masi M, Sautua F, Zatout R, Castaldi S, Arrico L, Isticato R, Pescitelli G, Carmona MA, Evidente A. Phaseocyclopentenones A and B, Phytotoxic Penta- and Tetrasubstituted Cyclopentenones Produced by Macrophomina phaseolina, the Causal Agent of Charcoal Rot of Soybean in Argentina. JOURNAL OF NATURAL PRODUCTS 2021; 84:459-465. [PMID: 33492968 DOI: 10.1021/acs.jnatprod.0c01287] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Two new penta- and tetrasubstituted cyclopentenones, named phaseocyclopentenones A and B (1 and 2), together with guignardone A (3), were isolated from Macrophomina phaseolina cultures. The phytopathogenic fungus was isolated from infected soybean tissues showing charcoal rot symptoms in Argentina. Charcoal rot is a devastating disease considering that soybean is one of the main legumes cultivated in the world. Phaseocyclopentenones A and B were characterized by 1D and 2D 1H and 13C NMR spectroscopic and HRESIMS spectrometric data and chemical methods as 4-benzoyl-3,4,5-trihydroxy-2-phenylcyclopent-2-enone and 3,5-dihydroxy-2,4-diphenylcyclopent-2-enone, respectively. The relative configuration of phaseocyclopentenones A and B was assigned by 1H and NOESY NMR methods, while their absolute configurations were assigned by electronic circular dichroism methods. When assayed on a nonhost plant (Solanum lycopersicum L.) by the leaf puncture assay, phaseocyclopentenones A and B and guignardone A showed phytotoxic activity, while only 1 and 2 were toxic when tested on cuttings of the same plant. No phytotoxicity or antifungal activity was detected for the three compounds on the host plant soybean (Glycine max L.) and against some of its fungal pathogens, namely, Cercospora nicotianae and Colletotrichum truncatum, also isolated from infected soybean plants in Argentina.
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Affiliation(s)
- Marco Masi
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Francisco Sautua
- Facultad de Agronomía, Cátedra de Fitopatología, Universidad de Buenos Aires, C1053 CABA Buenos Aires, Argentina
| | - Roukia Zatout
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
- Laboratoire de Mycologie, de Biotechnologie et de l'Activité Microbienne (LaMyBAM), Département de Biologie Appliquée, Université des Frères Mentouri, Constantine1, BP, 325 Route de Aïn El Bey, Constantine 25017, Algeria
| | - Stefany Castaldi
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Lorenzo Arrico
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Moruzzi 13, 56124 Pisa, Italy
| | - Rachele Isticato
- Dipartimento di Biologia, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
| | - Gennaro Pescitelli
- Dipartimento di Chimica e Chimica Industriale, Università di Pisa, Via Moruzzi 13, 56124 Pisa, Italy
| | - Marcelo Anibal Carmona
- Facultad de Agronomía, Cátedra de Fitopatología, Universidad de Buenos Aires, C1053 CABA Buenos Aires, Argentina
| | - Antonio Evidente
- Dipartimento di Scienze Chimiche, Università di Napoli Federico II, Complesso Universitario Monte S. Angelo, Via Cintia 4, 80126 Napoli, Italy
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Ganiu MO, Cleveland AH, Paul JL, Kartika R. Triphosgene and DMAP as Mild Reagents for Chemoselective Dehydration of Tertiary Alcohols. Org Lett 2019; 21:5611-5615. [PMID: 31251637 DOI: 10.1021/acs.orglett.9b01959] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
The utility of triphosgene and DMAP as mild reagents for chemoselective dehydration of tertiary alcohols is reported. Performed in dichloromethane at room temperature, this reaction is readily tolerated by a broad scope of substrates, yielding alkenes preferentially with the (E)-geometry. While formation of the Hofmann products is generally favored, a dramatic change in alkene selectivity toward the Zaitzev products is observed when the reaction is carried out in dichloroethane at reflux.
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Affiliation(s)
- Moshood O Ganiu
- Department of Chemistry , Louisiana State University , 232 Choppin Hall , Baton Rouge , Louisiana 70803 , United States
| | - Alexander H Cleveland
- Department of Chemistry , Louisiana State University , 232 Choppin Hall , Baton Rouge , Louisiana 70803 , United States
| | - Jarrod L Paul
- Department of Chemistry , Louisiana State University , 232 Choppin Hall , Baton Rouge , Louisiana 70803 , United States
| | - Rendy Kartika
- Department of Chemistry , Louisiana State University , 232 Choppin Hall , Baton Rouge , Louisiana 70803 , United States
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