13475-11-1

Upstream product

• 26239-07-6 5-methoxy-2,8,8-trimethyl-6,7-dihydro-4H,8H-benzo<1,2-b:5,4-b'>dipyran-4-one 
• 24128-11-8 6-Acetyl-5,7-dihydroxy-3,4-dihydro-2,2-dimethyl-2H-<1>benzopyran 
• 141-78-6 ethyl acetate 
• 119100-20-8 3-Acetyl-5-hydroxy-2,8,8-trimethyl-7,8-dihydro-6H-pyrano[3,2-g]chromen-4-one 
• 578-72-3 5,7-dihydroxy-2-methyl-6-(3-methyl-2-buten-1-yl)-4H-1-benzopyran-4-one 

Downstream Products

• 29507-75-3 spatheliachromen 

Relevant academic research and scientific papers

Heterocycles: Part 6 - Synthesis of Dihydroalloptaeroxylin, Dihydrospatheliachromene and Their Methyl Ethers

6-Acetyl-5,7-dihydroxy-2,2-dimethylchroman (1) on Kostanecki-Robinson reaction with anhyd. sodium acetate and acetic anhydride followed by 1:1 HCl treatment furnishes angular and linear 3-acetylchromones (2) and (3).Deacylation of 2 and 3 with aq.Na2CO3 yields dihydroalloptaeroxylin (4) and dihydrospatheliachromene (5) respectively.Compounds 4 and 5 on methylation give the corresponding methyl ethers 6 and 7.Alternatively 5 has been synthesized starting from 6-acetyl-7-hydroxy-5-methoxy-2,2-dimethyl-2H-chroman (8).

A New Synthesis of Alloptaeroxylin, Its Methyl Ether and Related Compounds

Claisen condensation of 6-acetyl-5,7-dihydroxy-2,2-dimethylchroman (I) with sodium and ethyl acetate gives isoheteropeucenin (II) and isopeucenin (III).Benzylic bromination of II and III with NBS followed by dehydrobromination with pyridine affords alloptaeroxylin (IV) and dehydroisopeucenin (V) respectively.IV on methylation gives alloptaeroxylin methyl ether (VI).VI has also been synthesized by an alternate route.