A Green and Efficient Synthesis of 1-Chloromethyl -2,3,4,5-Tetramethoxy-6-Methylbenzene

A convenient two-step synthesis of Coenzyme Q1

A convenient method for the preparation of Coenzyme Q1 from cheap and readily available 3,4,5-trimethoxytoluene is developed. Coenzyme Q1 is synthesized in a moderate yield by a two-step procedure involving the key reaction of an allyl bromide with Coenzyme Q0 through a redox chain reaction. The reaction is efficient and can be used for the synthesis of other Coenzyme Q compounds.

A convenient synthesis of 1,4-benzoquinones

A series of 1,4-benzoquinones was prepared in a high yield by a two-step reaction starting from 2,3,4,5-tetramethoxytoluene by a Blanc reaction and subsequent oxidation.

A convenient synthesis of 1-aralkyl-4-benzylpiperazine derivatives

An efficient two-step route was developed for the synthesis of 1-aralkyl-4-benzylpiperazine derivatives by a Blanc reaction and alkylation. The key intermediate, N-benzylpiperazine, was prepared in an excellent yield by direct benzylation of commercially available piperazine under metal-free conditions.

Efficient synthesis and antioxidant activities of N-heterocyclyl substituted Coenzyme Q analogues

A new strategy for the efficient synthesis of C-5 heterocyclyl substituted Coenzyme Q analogues was developed by N-alkylation of bromomethylated quinone 11 with a series of amines 12 under metal-free conditions. In vitro antioxidant activities of these Coenzyme Q analogues were evaluated and compared with commercial antioxidant Coenzyme Q10 by employing DPPH assay. All these N-heterocyclyl substituted Coenzyme Q analogues are found to be exhibiting good antioxidant properties and may be used as potent antioxidants for combating oxidative stress.

A novel Synthesis of Naringenin and Related Flavanones

Efficient methods are reported for the preparation of naringenin (4′,5,7-trihydroxyflavanone) which could be easily scaled-up. They have been applied to three other flavanones (6-hydroxyflavanone, 6,4′-dihydroxyflavanone, 6,3′,4′-trihydroxyflavanone) suitably.

Synthesis and antioxidant activities of Coenzyme Q analogues

A series of 2,3-dimethoxy-5-methyl-1,4-benzoquinones (Coenzyme Q) substituted at the C-6 position with various groups were designed and synthesized based on the Coenzyme Q10 as potent antioxidant. In vitro antioxidant activities of these compounds were evaluated and compared with commercial antioxidant Coenzyme Q10 employing DPPH assay. All these synthesized Coenzyme Q analogues are found to exhibit good antioxidant activities. Of which Compound 8b bearing a N-benzoylpiperazine group at the C-6 position showed more potent inhibition of DPPH radical than Coenzyme Q10. All these results suggested the applicability of the Coenzyme Q analogues as potent antioxidants for combating oxidative stress.

Total Synthesis of Luteolin

Luteolin is a naturally-occurring polyphenolic flavonoid compound which has received considerable attention because of its wide range of biological and pharmacological properties. Efficient methods are reported for preparing luteolin, based on the acylation of 1,3,5-trimethoxybenzene and condensation with 3,4-dimethoxybenzaldehyde or the reaction of 3,4-dimethoxycinnamic acid with 1,3,5-trimethoxybenzene. The first of these is the better method.

Total Synthesis of Apigenin

An efficient method for the synthesis of apigenin (4’,5,7-trihydroxyflavone, a traditional medicine) from phloroglucinol and anisaldehyde has been developed. This transformation features a green method for hydroxyl protection as methyl ethers and a different way for cyclisation using iodine in DMSO. The overall yield of 40% is satisfactory.

Alternative Synthesis of 2-(4-Benzoyl-Piperazin-1-Ylmethyl)-5, 6-Dimethoxy-3-Methyl-[1, 4]Benzoquinone

The title compound was prepared by a reaction sequence starting from 2, 3, 4, 5-tetramethoxytoluene via Blanc chloromethylation reaction, oxidation and alkylation. The described method provides a good yield of the heterocyclic-Coenzyme Q analogue and is suitable for the synthesis of other analogues.

A Facile Synthesis of 2, 3-Dimethoxy-5-Methyl-1, 4-Benzoquinones

Several 2, 3-dimethoxy-5-methyl-1, 4-benzoquinones substituted at the C-6 position with alkoxy methyl groups were prepared by a reaction sequence starting from 2, 3, 4, 5-tetramethoxytoluene (alkoxy methyl) via a Blanc chloromethylation reaction, Williamson reaction and oxidation. The method provided a good yield of 2, 3-dimethoxy-5-methyl-1, 4-benzoquinones and is suitable for the synthesis of other benzoquinone analogues.