- Synthesis and antioxidative activity of 3′,4′,6,7- tetrahydroxyaurone, a metabolite of Bidens frondosa
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3′,4′,6,7-Tetrahydroxyaurone (1a), an aurone isolated from Bidens frondosa, and five analogues (1b-1f) were synthesized from pyrogallol in three steps. The antioxidative activity of 1a-1f was determined by the superoxide free radical and 1,1-diphenyl-2-picrylhydrazyl (DPPH) free radical scavenging methods.
- Venkateswarlu, Somepalli,Panchagnula, Gopala K.,Subbaraju, Gottumukkala V.
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- Design and synthesis of new curcuminoid compounds and their derivatives as antioxidant agents
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A series of new curcumin analogues and their derivatives were synthesized by reacting curcumin analogues with various substituted hydrazine compounds to afford new pyrazol derivatives. The preparation of ether and ester derivatives was also carried out. All synthesized compounds were characterized using FT-IR, 1HNMR, 13CNMR, and MS-ESI. The evaluations of these compounds have shown a good inhibition activity as antioxidant agents against the stable radical of diphenylpicrylhydrazyl (DPPH). Findings from this work demonstrated a high inhibition activity in compounds substituted with hydroxyl phenol groups in comparison with compounds with other groups.
- Abood, Rehab G.,Alsalim, Tahseen A.,Abood, Einas A.
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p. 2173 - 2183
(2021/04/22)
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- Specificity of Calreticulin Transacetylase to acetoxy derivatives of benzofurans: Effect on the activation of platelet Nitric Oxide Synthase
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Calreticulin Transacetylase (CRTAase) catalyzes the transfer of acetyl group(s) from polyphenolic acetates (PAs) to functional proteins, such as Glutathione S-transferase (GST), NADPH Cytochrome c reductase and Nitric Oxide Synthase (NOS) resulting in the modulation of biological activities. A comparison of the specificities of the acetoxy derivatives of coumarins, biscoumarins, chromones, flavones, isoflavones and xanthones has been carried out earlier by us with an aim to study the effect of nature and position of the acetoxy groups on the benzenoid ring and the position of the carbonyl group with respect to oxygen/nitrogen heteroatom for the catalytic activity of CRTAase. In this communication for the first time, we have studied the influence of differently substituted benzofurans on the CRTAase activity to study the effect of the replacement of pyran ring of coumarin with furan ring, presence of carbonyl at C-3, substitution of C-3 carbonyl group with acetoxy group and presence of various substituents (OAc/OH/Cl) on the benzenoid ring. It was observed that acetoxy derivatives of benzofurans lead to inhibition of ADP induced platelet aggregation by the activation of platelet Nitric Oxide Synthase catalyzed by CRTAase. Accordingly, the formation of NO in platelets by 3-oxo-2,3-dihydrobenzofuran-6,7-diyl diacetate (3a) was found to be comparable with that of model polyphenolic acetate (PA), 7,8-diacetoxy-4-methylcoumarin (DAMC).
- Gupta, Anjali,Priya, Nivedita,Jalal, Sarah,Singh, Prabhjot,Chand, Karam,Raj, Hanumantharao G.,Parmar, Virinder S.,DePass, Anthony L.,Sharma, Sunil K.
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experimental part
p. 1180 - 1185
(2011/11/06)
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- A series of 2(Z)-2-benzylidene-6,7-dihydroxybenzofuran-3[2H]-ones as inhibitors of chorismate synthase
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A series of 2(Z)-2-benzylidene-6,7-dihydroxybenzofuran-3[2H]-ones was identified as potent inhibitors of bacterial chorismate synthase. The 2′-hydroxy-4′-pentoxy analogue 33 is a potent inhibitor of Streptococcus pneumoniae chorismate synthase.
- Thomas, Michael G.,Lawson, Chris,Allanson, Nigel M.,Leslie, Bruce W.,Bottomley, Joanna R.,McBride, Andrew,Olusanya, Oyinkan A.
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p. 423 - 426
(2007/10/03)
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- Process for making ω-chloro-2,3,4-trihydroxyacetophenone
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8-Methoxypsoralen is prepared in six steps from pyrogallol including condensation of pyrogallol with a two-fold excess of chloroacetic acid with boron trifluoride hydrogenation of 6,7-dihydroxy-2,3-dihydrobenzofuran and dehydrogenation of 2,3-dihydroxanthotoxin. Improvements in these three steps lead to a marked overall increase in yield.
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- 8-Methoxypsoralen
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8-Methoxypsoralen is prepared in six steps from pyrogallol including hydrogenation of 6,7-dihydroxy-2,3-dihydrobenzofuran and dehydrogenation of 2,3-dihydroxanthotoxin. Improvements in these two steps lead to a marked overall increase in yield.
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