“…Callistemon species are used traditionally for treating hemorrhoids and gastrointestinal and respiratory disorders. , Callistemon extracts have exerted antidiabetic, anti-inflammatory, antimicrobial, cytotoxic, , cardioprotective, and hepatoprotective effects . Recently, a series of triketone-phloroglucinol-monoterpene hybrids named “callistrilone” has been reported from C. rigidus . − In our present study, C. citrinus active extract was subjected to phytochemical investigation, which resulted in the isolation of three new structurally challenging meroterpenoids each existing in a distinct equilibrium mixture of two conformational isomers, named callistrilones L–N ( 1 – 3 ), together with 14 known compounds ( 4 – 17 ). The known compounds were identified as callistrilone E ( 4 ), , callistiviminene N ( 5 ), callistiviminen M ( 6 ), callistiviminene F ( 7 ), myrtucommulone L ( 8 ), calliviminone A ( 9 ), myrtucommulone K ( 10 ), callistiviminene I ( 11 ), callistenone D ( 12 ), endoperoxide G3 ( 13 ), 8-demethyleucalyptin ( 14 ), eucalyptin ( 15 ), catechin ( 16 ), and isoguaiacin ( 17 ) …”