TY  - JOUR
A1  - Gonzalez-Chavarria, Ivan
A1  - Duprat, Felix
A1  - Roa, Francisco J.
A1  - Jara, Nery
A1  - Toledo, Jorge R.
A1  - Miranda, Felipe
A1  - Becerra, Jose
A1  - Inostroza, Alejandro
A1  - Kelling, Alexandra
A1  - Schilde, Uwe
A1  - Heydenreich, Matthias
A1  - Paz, Cristian
T1  - Maytenus disticha extract and an isolated β-Dihydroagarofuran induce mitochondrial depolarization and apoptosis in human cancer cells by increasing mitochondrial reactive oxygen species
JF  - Biomolecules
N2  - Maytenus disticha (Hook F.), belonging to the Celastraceae family, is an evergreen shrub, native of the central southern mountains of Chile. Previous studies demonstrated that the total extract of M. disticha (MD) has an acetylcholinesterase inhibitory activity along with growth regulatory and insecticidal activities. beta-Dihydroagarofurans sesquiterpenes are the most active components in the plant. However, its activity in cancer has not been analyzed yet. Here, we demonstrate that MD has a cytotoxic activity on breast (MCF-7), lung (PC9), and prostate (C4-2B) human cancer cells with an IC50 (mu g/mL) of 40, 4.7, and 5 mu g/mL, respectively, an increasing Bax/Bcl2 ratio, and inducing a mitochondrial membrane depolarization. The beta-dihydroagarofuran-type sesquiterpene (MD-6), dihydromyricetin (MD-9), and dihydromyricetin-3-O-beta-glucoside (MD-10) were isolated as the major compounds from MD extracts. From these compounds, only MD-6 showed cytotoxic activity on MCF-7, PC9, and C4-2B with an IC50 of 31.02, 17.58, and 42.19 mu M, respectively. Furthermore, the MD-6 increases cell ROS generation, and MD and MD-6 induce a mitochondrial superoxide generation and apoptosis on MCF-7, PC9, and C4-2B, which suggests that the cytotoxic effect of MD is mediated in part by the beta-dihydroagarofuran-type that induces apoptosis by a mitochondrial dysfunction.
KW  - Maytenus disticha
KW  - beta-dihydroagarofuran-type sesquiterpene
KW  - dihydromyricetin
KW  - dihydromyricetin-3-O-beta-glucoside
KW  - cytotoxic
KW  - activity
KW  - Mitochondrial ROS
Y1  - 2020
U6  - https://doi.org/10.3390/biom10030377
SN  - 2218-273X
VL  - 10
IS  - 3
PB  - MDPI
CY  - Basel
ER  - 
TY  - JOUR
A1  - Paz, Cristian
A1  - Becerra, Jose
A1  - Silva, Mario
A1  - Burgos, Viviana
A1  - Heydenreich, Matthias
A1  - Schmidt, Bernd
A1  - Thu Tran, 
A1  - Vetter, Irina
T1  - (-)-Pentylsedinine, a New Alkaloid from the Leaves of Lobelia tupa with Agonist Activity at Nicotinic Acetylcholine Receptor
JF  - Natural product communications : an international journal for communications and reviews
N2  - Lobelia tupa, also called devil's tobacco, is a native plant from the center-south of Chile which has been used by the native people of Chile as a hallucinogenic and anesthetic plant. A new piperidine alkaloid, called pentylsedinine, which comprises five carbons in the side chain, was isolated from the aerial part of L. tupa, along with lobeline and lobelanidine. The structure was established on the basis of 1D and 2D NMR spectroscopy. While lobeline is a neutral antagonist at alpha 3 beta 2/alpha 3 beta 4 nAChR and alpha 7 nAChR, both lobelanidine and pentylsedinine act as partial agonists at nAChR
KW  - Lobelia tupa
KW  - Piperidine alkaloid
KW  - nAChR
KW  - Pentylsedinine
Y1  - 2015
SN  - 1934-578X
SN  - 1555-9475
VL  - 10
IS  - 8
SP  - 1355
EP  - 1357
PB  - NPC
CY  - Westerville
ER  - 
TY  - JOUR
A1  - Paz, Cristian
A1  - Becerra, Jose
A1  - Silva, Mario
A1  - Cabrera-Pardo, Jaime
A1  - Burgos, Viviana
A1  - Heydenreich, Matthias
A1  - Schmidt, Bernd
T1  - (-)-8-Oxohobartine a New Indole Alkaloid from Aristotelia chilensis (Mol.) Stuntz
JF  - Records of Natural Products
N2  - The fruit of Aristotelia chilensis is considered a "super fruit" due to its high concentration of polyphenols displaying exceptional antioxidant capacities ORAC. From maqui berries have been reported several anthocyanins and glycosylated flavonoids, those benefits increase the attention to restudy the plant. From the leaves of A. chilensis several indole alkaloids have been reported, we in addition to aristoteline, aristone, aristoquinoline and 3-fromylindole report the spectroscopic elucidation of 8-oxo-9-dehydromakomakine (1), hobartine (2) and a new alkaloid named 8-oxohobartine (3). Compound 1 to 3 did not show bactericidal activity against E. coli and S. aureus till 200 mu g.
KW  - Aristotelia chilensis
KW  - indole alkaloids
KW  - 8-oxohobartine
Y1  - 2016
SN  - 1307-6167
VL  - 10
SP  - 68
EP  - 73
PB  - ACG Publications
CY  - Gebze-Kocaeli
ER  - 
TY  - JOUR
A1  - Paz, Cristian
A1  - Peter, Martin G.
A1  - Schmidt, Bernd
A1  - Becerra, Jose
A1  - Gutierrez, Margarita
A1  - Astudillo, Luis
A1  - Silva, Mario
T1  - Synthesis and AChE inhibiting activity of 2, 4 substituted 6-Phenyl Pyrimidines
JF  - Journal of the Chilean Chemical Society
N2  - Novel substituted pyrimidines were synthesized from methyl 2,4-dioxo-4-phenyl-butanoate (I-A) and urea, followed by Mitsunobu coupling of I-A with benzyl or allyl alcohol to give the corresponding 2-hydroxypyrimidine ethers in good yields. Saponification of I-A, followed by reaction with benzyl or allyl amines in the presence of TBTU yielded 2-hydroxy-6-phenyl-pyrimidine 4-carboxamides. AChE and BuChE assays revealed 2-hydroxy-6-phenyl-pyrimidine-4-carboxyallyamide as the most active compound, IC50=90 mu M, with no inhibition of BuChE.
KW  - Pyrimidines
KW  - inhibition AChE
KW  - mitsunobu
KW  - TBTU
Y1  - 2012
SN  - 0717-9324
VL  - 57
IS  - 3
SP  - 1292
EP  - 1294
PB  - Sociedad Chilena De Quimica
CY  - Concepcion
ER  -