Chiral synthesis of (+)-8′-demethyl abscisic acid

1996 ◽  
Vol 74 (10) ◽  
pp. 1836-1843 ◽  
Author(s):  
Patricia A. Rose ◽  
Bo Lei ◽  
Angela C. Shaw ◽  
Suzanne R. Abrams ◽  
M. K. Walker-Simmons ◽  
...  
Keyword(s):  
Biological Activity ◽  
Abscisic Acid ◽  
Enantioselective Synthesis ◽  
Phenol Oxidation ◽  
Germination Inhibition ◽  
Embryo Germination ◽  
Chiral Synthesis ◽  
Wheat Embryo ◽  
Methyl Group ◽  
Key Words Abscisic Acid

An enantioselective synthesis of (+)-8′-demethyl ABA (2) is described. The chiral intermediate 7 was prepared by yeast reduction of a substituted monoprotected cyclohexa-2,5-dien-1,4-dione (9) synthesized through a phenol oxidation. The scope and limitations of the phenol oxidation is described. 8′-Demethyl ABA shows ABA-like activity in wheat embryo germination inhibition, showing that the 8′-methyl group is not essential for biological activity. Key words: abscisic acid, phenol oxidation, yeast reduction.

scholarly journals The 7[prime]-Methyl Group of Abscisic Acid Is Critical for Biological Activity in Wheat Embryo Germination

1994 ◽  
Vol 106 (4) ◽  
pp. 1279-1284 ◽  
Author(s):  
M. K. Walker-Simmons ◽  
P. A. Rose ◽  
A. C. Shaw ◽  
S. R. Abrams
Keyword(s):  
Biological Activity ◽  
Abscisic Acid ◽  
Embryo Germination ◽  
Wheat Embryo ◽  
Methyl Group

Interaction of abscisic acid and jasmonic acid on the inhibition of seed germination and the induction of freezing tolerance

1994 ◽  
Vol 72 (7) ◽  
pp. 1009-1017 ◽  
Author(s):  
Ronald W. Wilen ◽  
Bruce E. Ewan ◽  
Lawrence V. Gusta
Keyword(s):  
Abscisic Acid ◽  
Seed Germination ◽  
Jasmonic Acid ◽  
Freezing Tolerance ◽  
Lepidium Sativum ◽  
Detectable Effect ◽  
Suspension Cell Culture ◽  
Germination Inhibition ◽  
Cress Seed ◽  
Key Words Abscisic Acid

The possible interaction of the two growth regulators, abscisic acid and jasmonic acid, on the inhibition of seed germination and the induction of freezing tolerance in bromegrass (Bromus inermis Leyss) cell cultures was investigated. Both of these processes are known to be affected by exogenous abscisic acid. Alfalfa (Medicago sativa), cornflower (Centurae gynura), cress seed (Lepidium sativum), maize (Zea mays), and wheat (Triticum aestivum) seeds were treated with varying concentrations of abscisic acid and jasmonic acid, either alone or in combination. In all species, seed germination was inhibited by 10 μM abscisic acid at 23 °C. In contrast, at 23 °C, jasmonic acid was partially inhibitory only at 100 μM; however, 10 μM jasmonic acid inhibited germination in all species at 10 °C. Jasmonic acid in combination with abscisic acid resulted in a higher degree of germination inhibition at 23 °C in all species than either growth regulator applied separately. Treatment of a bromegrass suspension cell culture with 75 μM abscisic acid at 25 °C for 7 days increased the freezing tolerance from −10 °C to lower than −35 °C. In contrast, jasmonic acid (0.25–75 μM) had no detectable effect on freezing tolerance. Jasmonic acid in combination with suboptimal concentrations of abscisic acid, however, enhanced the abscisic acid-induced freezing tolerance in these cells. In contrast, a combination of 75 μM abscisic acid and 25 or 75 μM jasmonic acid reduced the freezing tolerance of these cells compared with treatment with abscisic acid alone. Key words: abscisic acid, freezing tolerance, germination, jasmonic acid.

scholarly journals Transcriptome Reveals Roles of Lignin-Modifying Enzymes and Abscisic Acid in the Symbiosis of Mycena and Gastrodia elata

2021 ◽  
Vol 22 (12) ◽  
pp. 6557
Author(s):  
Li-Ying Ren ◽  
Heng Zhao ◽  
Xiao-Ling Liu ◽  
Tong-Kai Zong ◽  
Min Qiao ◽  
...  
Keyword(s):  
Biological Activity ◽  
Abscisic Acid ◽  
Lignin Degradation ◽  
Molecular Mechanisms ◽  
Receptor Protein ◽  
Gastrodia Elata ◽  
Upregulated Genes ◽  
Aba Biosynthesis ◽  
Seed Coats

Gastrodia elata is a well-known medicinal and heterotrophic orchid. Its germination, limited by the impermeability of seed coat lignin and inhibition by abscisic acid (ABA), is triggered by symbiosis with fungi such as Mycena spp. However, the molecular mechanisms of lignin degradation by Mycena and ABA biosynthesis and signaling in G. elata remain unclear. In order to gain insights into these two processes, this study analyzed the transcriptomes of these organisms during their dynamic symbiosis. Among the 25 lignin-modifying enzyme genes in Mycena, two ligninolytic class II peroxidases and two laccases were significantly upregulated, most likely enabling Mycena hyphae to break through the lignin seed coats of G. elata. Genes related to reduced virulence and loss of pathogenicity in Mycena accounted for more than half of annotated genes, presumably contributing to symbiosis. After coculture, upregulated genes outnumbered downregulated genes in G. elata seeds, suggesting slightly increased biological activity, while Mycena hyphae had fewer upregulated than downregulated genes, indicating decreased biological activity. ABA biosynthesis in G. elata was reduced by the downregulated expression of 9-cis-epoxycarotenoid dioxygenase (NCED-2), and ABA signaling was blocked by the downregulated expression of a receptor protein (PYL12-like). This is the first report to describe the role of NCED-2 and PYL12-like in breaking G. elata seed dormancy by reducing the synthesis and blocking the signaling of the germination inhibitor ABA. This study provides a theoretical basis for screening germination fungi to identify effective symbionts and for reducing ABA inhibition of G. elata seed germination.

Hitting a Moving Target: How Does anN-Methyl Group Impact Biological Activity?

ChemMedChem ◽  
2016 ◽  
Vol 11 (8) ◽  
pp. 881-892 ◽  
Author(s):  
Yen Chin Koay ◽  
Nicole L. Richardson ◽  
Samantha S. Zaiter ◽  
Jessica Kho ◽  
Sheena Y. Nguyen ◽  
...  
Keyword(s):  
Biological Activity ◽  
Moving Target ◽  
Methyl Group

Biological activity of Pyraclostrobin against Coniella granati causing pomegranate crown rot

Plant Disease ◽  
2021 ◽  
Author(s):  
Xue Yang ◽  
Chun-Yan Gu ◽  
Yang Bai ◽  
Jia-Zhi Sun ◽  
Hao-Yu Zang ◽  
...  
Keyword(s):  
Biological Activity ◽  
Mycelial Growth ◽  
Field Trials ◽  
Crown Rot ◽  
Germination Inhibition ◽  
Control Efficacy ◽  
Intracellular Organelle ◽  
Transmission Electron ◽  
Excellent Control ◽  
Conidium Germination

Pomegranate crown rot caused by Coniellagranati is one of the most severe diseases of pomegranate. To date, no fungicides have been registered for controlling this disease in China. Pyraclostrobin, belonging to strobilurin fungicides, has a broad spectrum of activity against many phytopathogens. In this study, based on the mycelial growth and conidial germination inhibition methods, we investigated the biological activity of pyraclostrobin against C. granati at the presence of 50 μg/mL SHAM using 80 isolates collected from different orchards in China during 2012-2018. The EC50 (50% effective concentration) values ranged from 0.040-0.613 μg/mL for mycelial growth and 0.013-0.110 μg/mL for conidium germination, respectively. Treated with pyraclostrobin, the hyphae morphology changed and conidial production of C. granati decreased significantly. The result of transmission electron microscope showed that treatment of pyraclostrobin could make the cell wall thinner, and lead to ruptured cell membrane and formation of intracellular organelle autophagosomes. The pyraclostrobin showed good protective and curative activities against C. granati on detached pomegranate fruits. In field trials, pyraclostrobin showed excellent control efficacy against this disease in which the treatment of 25% pyraclostrobin EC 1000× provided 92.25% and 92.58% control efficacy in 2019 and 2020, respectively, significantly higher than that of other treatments. Therefore, pyraclostrobin could be a candidate fungicide for the control of pomegranate crown rot.

ChemInform Abstract: Ring Conformational Requirement for Biological Activity of Abscisic Acid Probed by the Cyclopropane Analogues.

ChemInform ◽  
2010 ◽  
Vol 27 (38) ◽  
pp. no-no
Author(s):  
Y. TODOROKI ◽  
S. NAKANO ◽  
N. HIRAI ◽  
H. OHIGASHI
Keyword(s):  
Biological Activity ◽  
Abscisic Acid

ChemInform Abstract: Enantiomers of 8-(3-tert-Butylamino-2-hydroxypropoxy)-3,4-dihydro-3- oxo-2H(1,4)benzothiazine: Racemic Resolution, Chiral Synthesis and Biological Activity.

ChemInform ◽  
2010 ◽  
Vol 22 (30) ◽  
pp. no-no
Author(s):  
F. SCHIAFFELLA ◽  
R. FRINGUELLI ◽  
V. CECCHETTI ◽  
A. FRAVOLINI ◽  
P. ANGELI ◽  
...  
Keyword(s):  
Biological Activity ◽  
Chiral Synthesis ◽  
Racemic Resolution
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