1
|
Wang L, Yan X, Li Y, Gao C, Liu J. Preparation and Characterization of Avermectin B2 Microcapsules and Effective Control of Root-Knot Nematodes. ACS OMEGA 2023; 8:13038-13047. [PMID: 37065056 PMCID: PMC10099129 DOI: 10.1021/acsomega.3c00244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/13/2023] [Accepted: 03/14/2023] [Indexed: 06/19/2023]
Abstract
Polyurethane microcapsules of avermectin B2 were prepared by means of interfacial polymerization with methylene diphenyl diisocyanate as the wall material and triethanolamine as the initiator. The microcapsules were characterized by scanning electron microscopy, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The surfaces of the microcapsules were found to be smooth and almost spherical, and the encapsulation efficiency was high. The avermectin B2 microcapsules exhibited a good diffusion-controlled sustained-release performance, giving a cumulative release rate of 91.81%. The results indicated that the polyurethane capsule protected against the photolysis of avermectin B2. Finally, the microcapsules exhibited good soil leaching properties and were able to control the population of root-knot nematodes with an efficacy of 80.80%.
Collapse
|
2
|
Li GH, Zhang KQ. Natural nematicidal metabolites and advances in their biocontrol capacity on plant parasitic nematodes. Nat Prod Rep 2023; 40:646-675. [PMID: 36597965 DOI: 10.1039/d2np00074a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Covering: 2010 to 2021Natural nematicidal metabolites are important sources of nematode control. This review covers the isolation and structural determination of nematicidal metabolites from 2010 to 2021. We summarise chemical structures, bioactivity, metabolic regulation and biosynthesis of potential nematocides, and structure-activity relationship and application potentiality of natural metabolites in plant parasitic nematodes' biocontrol. In doing so, we aim to provide a comprehensive overview of the potential roles that natural metabolites can play in anti-nematode strategies.
Collapse
Affiliation(s)
- Guo-Hong Li
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming, 650091, China.
| | - Ke-Qin Zhang
- State Key Laboratory for Conservation and Utilization of Bio-Resources in Yunnan, Key Laboratory for Southwest Microbial Diversity of the Ministry of Education, Yunnan University, Kunming, 650091, China.
| |
Collapse
|
3
|
Shen J, Zhang C, Zhang S, Chen F, Pei F, Zhou S, Lin H. Screening, isolation and mechanism of a nematicidal extract from actinomycetes against the pine wood nematode Bursaphelenchus xylophilus. Heliyon 2022; 8:e11713. [DOI: 10.1016/j.heliyon.2022.e11713] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/02/2022] [Revised: 05/06/2022] [Accepted: 11/11/2022] [Indexed: 11/18/2022] Open
|
4
|
Xu Q, Li J, Guo W, Xiang J, Zhou L, Zhang J. High Value Utilization of an Avermectin Fermentation Byproduct: Novel B2a Derivatives as Pesticide Candidates. JOURNAL OF AGRICULTURAL AND FOOD CHEMISTRY 2022; 70:6377-6384. [PMID: 35584200 DOI: 10.1021/acs.jafc.2c01035] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
In an effort to develop novel molecules with suitable insecticidal activities, 23,24-alkene-avermectin B2a derivatives have been synthesized via a one-pot multistep reaction using avermectin B2a, a byproduct of avermectin fermentation, as a starting material. All products and intermediates were characterized by 1H NMR, 13C NMR, and high-resolution mass spectrometry. Bioassay results showed that the LC50 values of compounds 4 and 9 against Meloidogyne incognita were 0.63 and 0.50 mg/L, respectively, similar to that of avermectin (0.46 mg/L). Importantly, the LC50 values of compound 9 against Tetranychus cinnabarinus and Mythimna separate were 0.0067 and 0.047 mg/L, respectively, superior to that of avermectin. Through field experiments, it could be found that spraying 0.25% water-dispersible granules of compound 9 345 g ha-1 could effectively control M. incognita outbreaks, with an efficacy of 84.9%. Combined with toxicity experiments, it could be further inferred that compound 9 may be useful as a low-toxicity pesticide. In summary, we efficiently synthesized a new B2a derivative as a potential pesticide and offered an important way for improving the utilization efficiency of avermectin fermentation products. In doing so, the environmental pollution associated with fermentation byproducts may be greatly reduced, potentially enabling a sustainable avermectin fermentation process.
Collapse
Affiliation(s)
- Qingbo Xu
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100094, China
| | - Jinming Li
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100094, China
| | - Wenxiu Guo
- Shandong Key Laboratory of Plant Virology, Institute of Plant Protection, Shandong Academy of Agricultural Sciences, Jinan 250100, China
| | - Juncheng Xiang
- Shanghai GreenTech Laboratory Co. Ltd., Shanghai 100093, China
| | - Liqi Zhou
- Shanghai GreenTech Laboratory Co. Ltd., Shanghai 100093, China
| | - Jianjun Zhang
- Innovation Center of Pesticide Research, Department of Applied Chemistry, College of Science, China Agricultural University, Beijing 100094, China
| |
Collapse
|
5
|
Liu XD, Gu KB, Xia SS, Zhang DJ, Li YG. Dolyemycins A and B, two novel cyclopeptides isolated from Streptomyces griseus subsp. griseus HYS31. J Antibiot (Tokyo) 2018; 71:838-845. [PMID: 29980746 DOI: 10.1038/s41429-018-0071-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 04/18/2018] [Accepted: 05/16/2018] [Indexed: 11/09/2022]
Abstract
Two novel cyclopeptides with special skeleton, namely, dolyemycins A (1) and B (2) were isolated from Streptomyces griseus subsp. griseus HYS31 by bio-guided isolation. Their structures were elucidated by detailed analysis of spectroscopic data. These two compounds were cyclopeptides containing eleven amino acids including five unusual amino acids (hydroxyglycine, 3-hydroxyleucine, 3-phenylserine, β-hydroxy-O-methyltyrosine, 2,3-diaminobutyric acid) in both of them and an extra nonprotein amino acids (3-methylaspartic acid) in Dolyemycin B only. Dolyemycins A and B performed antiproliferative activity against human lung cancer A549 cells with IC50 values of 1.0 and 1.2 µM, respectively.
Collapse
Affiliation(s)
- Xiao-Dong Liu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Kang-Bo Gu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Sha-Sha Xia
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China
| | - Dao-Jing Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
| | - Yuan-Guang Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, 200237, People's Republic of China.
| |
Collapse
|
6
|
Hou Z, Liang X, Du L, Su F, Su W. Quantitative determination and validation of avermectin B1a in commercial products using quantitative nuclear magnetic resonance spectroscopy. MAGNETIC RESONANCE IN CHEMISTRY : MRC 2014; 52:480-485. [PMID: 24943110 DOI: 10.1002/mrc.4098] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2014] [Revised: 05/01/2014] [Accepted: 05/30/2014] [Indexed: 06/03/2023]
Abstract
Nuclear magnetic resonance is defined as a quantitative spectroscopic tool that enables a precise determination of the number of substances in liquids as well as in solids. There is few report demonstrating the application of NMR in the quantification of avermectin B1a (AVB1a ); here, a proton nuclear magnetic resonance spectroscopy ((1) H NMR) using benzene [1-methoxy-4-(2-nitroethyl) (PMN)] as an internal standard and deuterochloroform as an NMR solvent was tested for the quantitative determination of AVB1a . The integrated signal of AVB1a at 5.56 ppm and the signal of PMN at 8.14 ppm in the (1) H NMR spectrum were used for quantification purposes. Parameters of specificity, linearity, accuracy, precision, intermediate precision, range, limit of detection (LOD), limit of quantification (LOQ), stability and robustness were validated. The established method was accurate and precise with good recovery (98.86%) and relative standard deviation (RSD) of assay (0.34%) within the linearity of the calibration curve ranging from 5.08 to 13.58 mg/ml (R(2) = 0.9999). The LOD and LOQ were 0.009 and 0.029 mg/ml, which indicated the excellent sensitivity of the method. The stability of the method was testified by a calculated RSD of 0.11%. The robustness was testified by modification of four different parameters, and the differences among each parameter were all less than 0.1%. Comparing with the assay described by the manufacturer of avermectin tablets, there was no significant difference between the assay obtained by HPLC and quantitative NMR (qNMR), which indicated qNMR was a simple and efficient method for the determination of AVB1a in commercial formulation products.
Collapse
Affiliation(s)
- Zhuoni Hou
- Key Laboratory for Green Pharmaceutical Technologies and Related Equipment of Ministry of Education, College of Pharmaceutical Sciences, Zhejiang University of Technology, Hangzhou, 310014, China
| | | | | | | | | |
Collapse
|
7
|
Zong G, Zhao H, Jiang R, Zhang J, Liang X, Li B, Shi Y, Wang D. Design, synthesis and bioactivity of novel glycosylthiadiazole derivatives. Molecules 2014; 19:7832-49. [PMID: 24962389 PMCID: PMC6271630 DOI: 10.3390/molecules19067832] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2014] [Revised: 06/04/2014] [Accepted: 06/05/2014] [Indexed: 11/18/2022] Open
Abstract
A series of novel glycosylthiadiazole derivatives, namely 2-phenylamino-5-glycosyl-1,3,4-thiadiazoles, were designed and synthesized by condensation between sugar aldehydes A/B and substituted thiosemicarbazide C followed by oxidative cyclization by treating with manganese dioxide. The original fungicidal activities results showed that some title compounds exhibited excellent fungicidal activities against Sclerotinia sclerotiorum (Lib.) de Bary and Pyricularia oryzae Cav, especially compounds F-5 and G-8 which displayed better fungicidal activities than the commercial fungicide chlorothalonil. At the same time, the preliminary studies based on the Elson-Morgan method indicated that many compounds exhibited some inhibitory activity toward glucosamine-6-phosphate synthase (GlmS). The structure-activity relationships (SAR) are discussed in terms of the effects of the substituents on both the benzene and the sugar ring.
Collapse
Affiliation(s)
- Guanghui Zong
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| | - Hanqing Zhao
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| | - Rui Jiang
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| | - Jianjun Zhang
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China.
| | - Xiaomei Liang
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| | - Baoju Li
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China
| | - Yanxia Shi
- Institute of Vegetables and Flowers, Chinese Academy of Agricultural Sciences, Beijing 100081, China.
| | - Daoquan Wang
- Department of Applied Chemistry, China Agricultural University, Beijing 100193, China
| |
Collapse
|
8
|
Xu Q, Xiang W, Li J, Liu Y, Yu X, Zhang Y, Qu M. Development and validation of an HPLC-FLD method for milbemectin quantification in dog plasma. J Chromatogr B Analyt Technol Biomed Life Sci 2010; 878:2013-7. [PMID: 20573552 DOI: 10.1016/j.jchromb.2010.05.037] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2010] [Revised: 04/29/2010] [Accepted: 05/24/2010] [Indexed: 11/29/2022]
Abstract
Milbemectin is a widely used veterinary antiparasitic agent. A high-performance liquid chromatography with fluorescent detection (HPLC-FLD) method is described for the determination of milbemectin in dog plasma. The derivative procedure included mixing 1-methylimizole [MI, MI-ACN (1:1, v/v), 100 microL], trifluoroacetic anhydride [TFAA, TFAA-ACN (1:2, v/v), 150 microL] with a subsequent incubation for 3s at the room temperature to obtain a fluorescent derivative, which is reproducible in different blood samples and the derivatives proved to be stable for at least 80 h at room temperature. HPLC method was developed on C18 column with FLD detection at an excitation wavelength of 365 nm and emission wavelength of 475 nm, with the mobile phase consisting of methanol and water in the ratio of 98:2 (v/v). The assay lower limit of quantification was 1 ng/mL. The calibration curve was linear over concentration range of 1-200 ng/mL. The intra- and inter-day accuracy was >94% and precision expressed as % coefficient of variation was <5%. This method is specific, simple, accurate, precise and easily adaptable to measure milbemycin in blood of other animals.
Collapse
Affiliation(s)
- Qianqian Xu
- College of Veterinary, Northeast Agricultural University, 59 Mucai Street, Xiangfang District, 150030 Harbin, China
| | | | | | | | | | | | | |
Collapse
|
9
|
Copping LG, Duke SO. Natural products that have been used commercially as crop protection agents. PEST MANAGEMENT SCIENCE 2007; 63:524-54. [PMID: 17487882 DOI: 10.1002/ps.1378] [Citation(s) in RCA: 218] [Impact Index Per Article: 12.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/15/2023]
Abstract
Many compounds derived from living organisms have found a use in crop protection. These compounds have formed the basis of chemical synthesis programmes to derive new chemical products; they have been used to identify new biochemical modes of action that can be exploited by industry-led discovery programmes; some have been used as starting materials for semi-synthetic derivatives; and many have been used or continue to be used directly as crop protection agents. This review examines only those compounds derived from living organisms that are currently used as pesticides. Plant growth regulators and semiochemicals have been excluded from the review, as have living organisms that exert their effects by the production of biologically active secondary metabolites.
Collapse
|
10
|
Christie PT, Wright DJ. Activity of abamectin against larval stages ofSpodoptera littoralisboisduval andHeliothis armigerahübner (Lepidoptera: Noctuidae) and possible mechanisms determining differential toxicity. ACTA ACUST UNITED AC 2006. [DOI: 10.1002/ps.2780290105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
11
|
Wei L, Wei G, Zhang H, Wang PG, Du Y. Synthesis of new, potent avermectin-like insecticidal agents. Carbohydr Res 2005; 340:1583-90. [PMID: 15922315 DOI: 10.1016/j.carres.2005.04.019] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2005] [Accepted: 04/22/2005] [Indexed: 11/29/2022]
Abstract
4'-Modified avermectin derivatives were designed and synthesized. Some of the new synthetic compounds showed excellent in vivo bioactivity against cabbage larvae when compared to commercially available avermectin B1a. In this synthesis, uncommon thioglycosyl sugar donors, prepared from the hydrolysis of natural antibiotics, proved compatible with sugar-macrolide synthesis in the presence of N-iodosuccinimide (NIS) or I2 in N-methylpyrrolidone at room temperature.
Collapse
Affiliation(s)
- Lijun Wei
- School of Chemistry and Material Engineering, Yunnan University, Kunming City, Kunming 650091, China
| | | | | | | | | |
Collapse
|
12
|
Ming-Kun F, Xian W, Jun N, Jian-Zhong L. Solid Phase Synthesis of 4″-epi-Methylamino-4″-deoxyavermectin B1 Benzoate. CHINESE J CHEM 2005. [DOI: 10.1002/cjoc.200590901] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
|
13
|
Wei G, Du Y, Linhardt RJ. New potent insecticidal agent: 4′-fucosyl avermectin derivative. Tetrahedron Lett 2004. [DOI: 10.1016/j.tetlet.2004.07.092] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
|
14
|
Argentine JA, Jansson RK, Starner VR, Halliday WR. Toxicities of emamectin benzoate homologues and photodegradates to Lepidoptera. JOURNAL OF ECONOMIC ENTOMOLOGY 2002; 95:1185-1189. [PMID: 12539830 DOI: 10.1603/0022-0493-95.6.1185] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
The toxicity of a number of emamectin benzoate homologues and photodegradates to five species of Lepidoptera was investigated using diet and foliar bioassays. The emamectin benzoate homologues B1a and B1b were equally toxic in the diet and foliar assays to Spodoptera exigua (Hübner), Heliothis virescens (F.), Tricoplusia ni (Hübner), and Spodoptera frugiperda (J. E. Smith), within each of these species. Plutella xylostella (L.) was the most sensitive species to emamectin benzoate. The AB1a photodegradate of emamectin benzoate was as toxic as the parent compound in the diet assay. However, in the foliage assay AB1a was 4.4-fold less toxic to S. exigua than the parent compound. The MFB1a photodegradate of emamectin benzoate was as toxic as the parent compound to P. xylostella, and 3.1 to 6.2 times as toxic as the parent compound to the other species in the diet assay. The order of toxicity of the photodegradates were AB1a > MFB1a > FAB1a > 8,9-Z-MAB1a > PAB1a.
Collapse
|
15
|
Cvetovich RJ, Amato JS, DiMichele L, Weinstock L, Hazen G. Novel Electrochemical Reductive Amination of 4‘‘-Oxo-5-O-(tert-butyl- dimethylsilyl)avermectin B1. J Org Chem 1997. [DOI: 10.1021/jo970676l] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- Raymond J. Cvetovich
- Department of Process Research, Merck Research Laboratories, Division of Merck & Company, Inc., P.O. Box 2000, Rahway, New Jersey 07065
| | - Joseph S. Amato
- Department of Process Research, Merck Research Laboratories, Division of Merck & Company, Inc., P.O. Box 2000, Rahway, New Jersey 07065
| | - Lisa DiMichele
- Department of Process Research, Merck Research Laboratories, Division of Merck & Company, Inc., P.O. Box 2000, Rahway, New Jersey 07065
| | - Leonard Weinstock
- Department of Process Research, Merck Research Laboratories, Division of Merck & Company, Inc., P.O. Box 2000, Rahway, New Jersey 07065
| | - George Hazen
- Department of Process Research, Merck Research Laboratories, Division of Merck & Company, Inc., P.O. Box 2000, Rahway, New Jersey 07065
| |
Collapse
|
16
|
Mrozik H, Eskola P, Arison BH, Linn BO, Lusi A, Matzuk A, Shih TL, Tischler M, Waksmunski FS, Wyvratt MJ, Blizzard TA, Margiatto GM, Fisher MH, Shoop WL, Egerton JR. 4″-Deoxy-4″-aminoavermectins with potent broad spectrum antiparasitic activities. Bioorg Med Chem Lett 1995. [DOI: 10.1016/0960-894x(95)00424-r] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
|
17
|
Shoop WL, Mrozik H, Fisher MH. Structure and activity of avermectins and milbemycins in animal health. Vet Parasitol 1995; 59:139-56. [PMID: 7483237 DOI: 10.1016/0304-4017(94)00743-v] [Citation(s) in RCA: 312] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2023]
Abstract
The avermectins and, to a lesser extent, the milbemycins, have revolutionized antiparasitic and antipest control over the last decade. Both avermectins and milbemycins have macrocyclic lactone structures that are superimposable, they are produced by the same genus of soil dwelling organisms, they have the same mode of action, they exert this action against the same nematode/acarine/insect spectrum of targets, and they show the same mechanism-based toxicity in mammals. Reports suggesting that milbemycins have a different mode of action from avermectins with implications that there will be no mutual resistance to the groups have been shown to be false. Contributing to the belief that there were differences in mode of action between the two groups are the vague definitions of resistance presently in use which rely on the ability of the parasite to survive treatment at the manufacturer's recommended use level. More appropriately, drug resistance should be defined as 'a change in gene frequency of a population, produced by drug selection, which renders the minimal, effective dosage previously used to kill a defined portion (e.g. 95%) of the population no longer equally effective'. This type of definition would allow us to detect changes in susceptibility of a population earlier and is essential when comparing different chemicals to determine if there is mutual resistance to them. It is concluded that much effort has been expended by pharmaceutical, government, and academic scientists searching for broad-spectrum second generation avermectin and milbemycin products, but none has exceeded the original avermectin in any fundamental way. The newer avermectin and milbemycin compounds that have appeared claim niches in the market place based on emphasis of certain narrow parts of the overall spectrum. Consequently, there are no second generation avermectins and milbemycins at present and all newer compounds from this mode of action class are viewed as siblings of the first generation.
Collapse
Affiliation(s)
- W L Shoop
- Merck Research Laboratories, Rahway, NJ 07065-0900, USA
| | | | | |
Collapse
|
18
|
New, potent anthelmintic and acaricidal agents: 4″-deoxy-4″-thio-substituted avermectin derivatives. Bioorg Med Chem Lett 1993. [DOI: 10.1016/s0960-894x(01)80740-x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
19
|
Meinke PT, Sinclair P, Mrozik H, O'Connor S, Ostlind D, Shoop W, Arison B, Fisher MH. Synthesis of avermectin B1-4″,4″a-oxide: a precursor of potent anthelmintic agents. Bioorg Med Chem Lett 1992. [DOI: 10.1016/s0960-894x(01)81193-8] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
|
20
|
Fraser-Reid B, Cristóbal López J, Faghih R. The C4-exo methylene isomer of avermectin B1a: Synthesis via an allylic radical and bioactivity. Tetrahedron 1992. [DOI: 10.1016/s0040-4020(01)89865-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
|
21
|
Chapter 17. Antiparasitic Agents. ANNUAL REPORTS IN MEDICINAL CHEMISTRY 1991. [DOI: 10.1016/s0065-7743(08)61204-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register]
|