New chromomoric acid derivatives from Tectona philippinensis and other secondary metabolites from Philippine medicinal plants

A total of twelve compounds were isolated from the six Philippine medicinal plants covered in this study. The DCM extract of the air-dried leaves of Tectona philippinensis afforded three new chromomoric acid derivatives (Te7, Te5, and Te6). Their structures were elucidated by extensive 1D and 2D NMR spectroscopy and MS. Te7 Te5 Te6 The air-dried leaves of Pycnarrhena manillensis afforded two known compounds namely; stigmast-4-en-3,6-dione (NT1) and stigmast-4-en-3-one (NT9). Their structures were elucidated by 1D and 2D NMR spectroscopy. Two known compounds, 2,2’:5’,2’’-terthiophene (MG1) and 5,7,4’- trihyfroxyflavone (MG24b) were isolated from the DCM extract of the air-dried flowers of Tagetes erecta. The structure of MG1 was elucidated by 1D and 2D NMR spectroscopy while MG24b was identified by comparison of its 1 H and 13C NMR spectral data with those found in the literature The flavonone, Eriodictyol (Hb20) was obtained from the air-dried flowers of Helichrysum bracteatum. The structure of Hb20 was confirmed by comparison of its 1 H and 13C NMR spectral data with those in the literature. A sesquiterpene germacranolide, 11,13-dehydrolanuginolide (CH1) was isolated from the DCM extract of the air-dried flowers of Michelia champaca. CH1 was elucidated by 1D and 2D NMR spectroscopy. The air-dried flowers of Tithonia diversifolia afforded three known compounds; Tagitinin C (HA19), faradiol ester (HA15), and squalene (HA1). Tagitinin C was elucidated by 1D and 2D NMR spectroscopy. Ha15 and HA1 were identified by comparison of their 1 H and 13C NMR spectral data with those in the literature. The anti-microbial tests on HA19 indicated slight to moderate anti-microbial properties on the microorganisms employed