Cytotoxic amides have been isolated from the fruits of the endemic New Zealand medicinal plant kawakawa, Macropiper excelsum (Piperaceae). The main amide was piperchabamide A and this is the first report of this rare compound outside the genus Piper. Eleven other amides were purified including two new compounds with the unusual 3,4-dihydro-1(2H)-pyridinyl group. The new compounds were fully characterized by 2D NMR spectroscopy, which showed a slow exchange between two rotamers about the amide bond, and they were chemically synthesized. In view of the antitumor activity of the related piperlongumine, all of these amides plus four synthetic analogs were tested for cytotoxicity. The most active was the piperine homolog piperdardine, with an IC50 of 14 µM against HT 29 colon cancer cells.
Pharmacology, Toxicology and Pharmaceutical Science
2
6%
Immunology and Microbiology
2
6%
Biochemistry, Genetics and Molecular Biology
1
3%
Other
3
9%
Unknown
17
49%
Attention Score in Context
Attention Score in Context
This research output has an Altmetric Attention Score of 1. This is our high-level measure of the quality and quantity of online attention that it has received. This Attention Score, as well as the ranking and number of research outputs shown below, was calculated when the research output was last mentioned on 04 June 2015.
All research outputs
#18,412,793
of 22,808,725 outputs
Outputs from Planta Medica
#2,455
of 2,876 outputs
Outputs of similar age
#192,827
of 267,100 outputs
Outputs of similar age from Planta Medica
#24
of 37 outputs
Altmetric has tracked 22,808,725 research outputs across all sources so far. This one is in the 11th percentile – i.e., 11% of other outputs scored the same or lower than it.
So far Altmetric has tracked 2,876 research outputs from this source. They typically receive a little more attention than average, with a mean Attention Score of 5.4. This one is in the 10th percentile – i.e., 10% of its peers scored the same or lower than it.
Older research outputs will score higher simply because they've had more time to accumulate mentions. To account for age we can compare this Altmetric Attention Score to the 267,100 tracked outputs that were published within six weeks on either side of this one in any source. This one is in the 16th percentile – i.e., 16% of its contemporaries scored the same or lower than it.
We're also able to compare this research output to 37 others from the same source and published within six weeks on either side of this one. This one is in the 24th percentile – i.e., 24% of its contemporaries scored the same or lower than it.
