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29 Cards in this Set
- Front
- Back
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19th century
isolation morphine |
A “paradigm shift” in drug discovery occurred in the early ___, marked by the ___ of pure bioactive entities from medicinal plants, beginning with the isoquinoline alkaloid, ___
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atropine
cocaine codeine digitoxin quinine |
The purification of plant drug molecules such as ___, ___, ____, ___, ___ and ___, was also carried on later in the 19th century
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artemisinin,
digoxin, paclitaxel, vinblastine, vincristine. |
In the 20th century, additional important drugs were isolated from plants, including (5)
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pharmacology ; physicians ;pharmacists ; plant extractives
pure naturally occurring and synthetically modified; totally synthetic |
Also in the 20th century, as a result of advances made in ___and a better understanding of human diseases at the molecular level,__and ___gradually shifted from the use of ___in prescriptions to __natural products, or___ compounds.
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bioactive
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Today, the effort to find new ___principles from med.plants may bring together scientists working in a diverse range of disciplines.
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molecular biology
bioassays “mode of action” molecular |
The advances in ___ are duly reflected in the complexity of ___employed in the medicinal plant drug discovery field, and also provide the ___ information at the ___ level in a rapid and accurate fashion
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in vitro
in vivo |
Preliminary ___ experiments may then be followed up with a variety of___ bioassays.
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Terrestrial
organisms plethora synthetic chemists. |
___plants and other __ are known to be sources of a ___ of small organic molecules, representing considerable structural diversity, which may not be matched by the creativity of___
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chemical
bioactive |
When all currently known ___ entities are taken into consideration, the area of chemical space
occupied by ___ molecules is a relatively limited one. |
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Natural products
synthetic combinatorial |
___ have been found to account for much greater chemical diversity than compounds generated by both ___ and ___chemistry methods together.
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natural product
combinatorial chemistry more bioactive part synthetic |
Accordingly, libraries of pure ___, when combined with the advantages of ___, offer an even
more effective and reliable avenue for exploring the “___” of chemical space when compared with a purely ___ approach |
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single bonds
protonated amino free hydroxyl aromatic rings |
Natural products are significantly different from synthetic- and combinatorial chemistry-produced
compounds in that they have more ___, and ___ and ___ groups, while having fewer ___ |
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natural
ring systems rigid |
Also, ___compounds possess a greater diversity of ___ and tend to be more
___ than their synthetic counterparts |
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chiral
fewer rotatable bonds |
Natural products also exhibit more ___ centers and ___ than substances produced by synthesis
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“rule of five,”
physicochemical |
The ___ developed originally to guide the efforts of combinatorial chemistry, has spearheaded a new approach to drug discovery by defining the ___ characteristics a “drug-like” molecule should have
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natural products
proprietary drugs drug likeness |
comparison studies have shown that ___ resemble ___ and show a high degree of “___,” compared to their synthetic counterparts.
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evolutionary perspective
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Intricate biosynthetic proc.leading 2 bioactive sec metabolites frm organm w/bioactivity cont, 2 b maj. rsearch interest&there's been much thought as 2 how and why cpds.r biosynth. Most widely accepted &satisfactory explanations refer 2 an ___
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“primary metabolites”
life |
The presence of crucial building molecules, the __ (AA, FA, nucleosides,&sugars) can be considered synonymous with “___” since they are ubiquitous among all organisms.
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secondary metabolites
survival |
small-molecule organic cpds of considerable structural diversity and limited taxonomical
distribution, the ___,” are believed to provide the producing organisms with a ___ advantage |
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secondary metabolites
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organisms lacking immune systems
(e.g. higher and lower plants, algae, fungi and microorganisms) generally show a high abundance of these compounds called ___ |
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secondary metabolite
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The term “natural product” is usually used interchangeably with “___” for the
purposes of drug discovery from organisms |
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preserved
biosynthetic modification eliminated evolutionary pressure |
It has been argued that over millions of years, the cpds providing a survival advantage are ___(and even fine-tuned structurally through___), while the not-so-active analogues are___through ___
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enzyme
protein |
Secondary metabolites mostly exert their effects by acting through ___ or ___ interactions
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substrates
receptor endogenous disrupt |
While some of these sec. metabolites act as ___ at the ___level and mimic the ___ substances in the target organism, others simply ___ protein-protein interactions necessary for normal cell function
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secondary metabolites
physiology drug-like |
it might be concluded that it is this ability of ___ to interact with the ___ of other species that renders them as an impressive source of “evolutionarily fine-tuned” ___ molecules.
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chromatographic methods; reproducible
spectroscopic methods; structural characterization chemical methods bioactive lead compounds; |
Drug disc frm plants - evolving cont in resp 2 rec tech adv, e.g. devt of __ for &fast purifn 4 div. cpd classes; sensitive__ for___ of samp; eff___ 4 syn, deriv., &opt of ___& bioassays for chemist w/ crit info 2 target bioactive cpds frm stages of sep.
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organism collection, extraction, compound isolation, structure determination, and bioassay
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The standard practice in plant natural products isolation chemistry
for drug discovery can be broken down into five steps, namely ... |
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solvent
pharmacologically isolation studies activity-guided fractionation |
Plant samp r authd taxon& extracted w/ __ of choice and res. extracts r screened against __ relevant targets. If +result is achieved,_ follow, guided by relevant bioassay studies using the so-called “__” technique.
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spectroscopic
spectrometric Xray crystallographic |
When an active principle is isolated, thorough __ and __ or __methods are employed as needed for the unambiguous assignment of its structure and configuration
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