Fernando Cabieses

Compounds obtained from Sida acuta with the potential to induce quinone reductase and to inhibit 7,12-dimethylbenz-[ a]anthracene-induced preneoplastic lesions in a mouse mammary organ culture model

Activity-guided fractionation of the EtOAc-soluble extract of the whole plants ofSida acuta using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells, led to the isolation of ten active compounds of previously known structure, quindolinone (1), cryptolepinone (2), 11-methoxyquindoline (3),N-trans-feruloyltyramine (4), vomifoliol (5), loliolide (6), 4-ketopinoresinol (7), scopoletin (8), evofolin-A (9), and evofolin B (10), along with five inactive compounds of known structure, ferulic acid, sinapic acid, syringic acid, (±)-syringaresinol, and vanillic acid. These isolates were identified by physical and spectral data measurement. A new derivative of quindolinone, 5,10-dimethylquindolin-11-one (1a) was synthesized and characterized spectroscopically. Of the active substances, compounds1-3 and1a exhibited the most potent QR activity, with observed CD (concentration required to double induction) values ranging from 0.01 to 0.12 μg/mL. Six compounds were then evaluated in a mouse mammary organ culture assay, with cryptolepinone (2),N-trans-fer-uloyltyramine (4), and 5,10-dimethylquindolin-11-one (1a) found to exhibit 83.3, 75.0, and 66.7% inhibition of 7,12-dimethylbenz[a]anthracene-induced preneoplastic lesions, respectively, at a dose of 10 μg/mL.

Antimycobacterial evaluation of Peruvian plants.

We present the results of an antimycobacterial screening of 270 Peruvian plant samples representing 216 species from 171 genera in 63 families. Dichloromethane extracts were tested at a concentration of 50 microg/ml for inhibition of Mycobacterium tuberculosis in radiometric culture. Slightly more than half of the samples tested showed inhibition of M. tuberculosis at this concentration.

Phenolic compounds obtained from stems of Couepia ulei with the potential to induce quinone reductase

Activity-guided fractionation of the EtOAc-soluble extract of the stems of Couepia ulei, using a bioassay based on the induction of quinone reductase (QR) in cultured Hepa 1c1c7 mouse hepatoma cells led to the isolation of two active compounds, a new natural product,erythro-2,3-bis(4-hydroxy-3-methoxyphenyl)-3-ethoxypropan-1-ol (1), and a known compound, evofolin-B (2), along with five inactive compounds all of known structure, viz., betulinic acid, oleanolic acid, pomolic acid, (±)-syringaresinol, and ursolic acid. These isolates were identified by analysis of physical and spectral data. Compounds1 and2 exhibited QR inducing activity, with observed CD (concentration required to double induction) values of 16.7 and 16.4 μM, respectively.