5302-74-9

Upstream product

• 31525-67-4 dimethylacetal of 3-methyl-3-hydroxybutyraldehyde 
• 98192-65-5 5,7-Dihydroxy-8-(2-methylbutanoyl)-4-phenyl-2H-chromen-2-one 
• 108-73-6 3,5-dihydroxyphenol 
• 98-86-2 acetophenone 
• 94-02-0 ethyl 3-oxo-3-phenylpropionate 
• 125074-06-8 2-methyl-1-(2,4,6-trihydroxyphenyl)-1-butanone 
• 5856-79-1 iso-butyl chloroformate 

Downstream Products

• 161633-70-1 5-Methoxy-2,2-dimethyl-6-(2-methylbutanoyl)-10-phenyl-2H,8H-benzo<1,2-b:3,4-b'>dipyran-8-one 
• 41135-08-4 (+/-)-Inophyllum B 
• 41135-08-4 (+/-)-Inophyllum D 
• 41135-08-4 (+/-)-Inophyllum A 
• 41135-08-4 (10R,11S,12R)-12-Hydroxy-6,6,10,11-tetramethyl-4-phenyl-11,12-dihydro-6H,10H-dipyrano[2,3-f;2',3'-h]chromen-2-one 
• 172805-13-9 6-(2-Bromo-2-methylbutanoyl)-5-methoxy-2,2-dimethyl-10-phenyl-2H,8H-benzo<1,2-b:3,4-b'>dipyran-8-one 
• 172805-18-4 5-Hydroxy-2,2-dimethyl-6-<(E)-2-methylbut-2-enoyl>-10-phenyl-2H,8H-benzo<1,2-b:3,4-b'>dipyran-8-one 
• 548-27-6 calophyllolide 
• 548-28-7 (+/-)-Inophyllum C 

Relevant academic research and scientific papers

Synthesis of the Calophyllum coumarins. Part 2

Synthetic routes leading to the synthesis of the natural 4-phenyl, 4-propyl and 4-methyl coumarins isolated from Calophyllum sp. are presented. 4-Aryl or -alkyl, 8- and 6-acyl 5,7-dihydroxy coumarins were chromenylated and then methylated at the 5 or 7 positions.A 4-step hydrobromination-bromination-double dehydrobromination sequence converted the 2-methylbutanoyl side chain into the (E)-2-methylbut-2-enoyl (tigloyl) group to give calophyllolide, oblongulide, their natural 4-propyl analogue and the corresponding regioisomers.Demethylation and cyclisation of the tigloyl group gave inophyllums C and E, tomentolides A and B, and calanolide D.Sodium boranuide reduction of the 2,3-dimethylchromanone ring afforded inophyllums A, B, D and P, soulattrolide, calanolides A-C, costatolide, and cordatolides A and B.The structures of calanolides C and D, oblongulide and apetatolide have been reassigned.The previously unknown stereochemistry about the 2,3-dimethylchromanone ring of tomentolides A and B has been established as trans.

Synthesis of the calophyllum coumarins

Synthetic routes leading to the synthesis of the natural 4-alkyl and 4- phenyl coumarins isolated from Calophyllum sp. are reported. The reported structures of calanolides C and D and oblongutide are incorrect and have been corrected by unambiguous synthesis.

Synthesis of Mammea Coumarins. Part 1. The Coumarins of the Mammea A, B, and C Series

The naturally-occuring Mammea coumarins of the 4-phenyl-(mammea A), propyl-(mammea B), and 4-pentyl-(mammea C) series have been prepared by Pechmann condensation of an acylphloroglucinol (3-methylbutyryl-, 2-methylbutyryl-, butyryl-, or 2-methylpropionyl-) with the appropriate β-ketoester to give a mixture of 6- and 8-acyl-5,7-dihydroxycoumarins that could be separated.C-Alkylation with 3-methylbut-2-enyl bromide, or 3,7-dimethylocta-2,6-dienyl chloride, in aqueous potassium hydroxide completed the synthesis of the Mammea coumarins having unmodified prenyl or geranyl substituents; oxidative modification of the prenyl group led to the mammea cyclo E and cyclo F coumarins.Some mammea cyclo D (chromeno) coumarins were synthesized by reaction of acylcoumarins with 1,1-dimethoxy-3-methylbutan-3-ol.