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The following message was posted to: PharmPK
Dear Colleague,
Quantum Pharmaceuticals - a computational chemistry
software developer, presents its new LogP Calculation Software.
Quantum LogP software predicts octanol-water partition coefficient,
LogP,
for any small organic molecule (both charged and non-charged molecular
structures),
calculates LogD for dissociative systems at a given pH, and estimates
drug-likeness. The accuracy of calculations for most structures is
about 0.7
logP units. The results of calculations are represented in
logarithmic (LogP)
units.
ADVANTAGE OF QUANTUM COMPUTATIONAL CHEMISTRY SOFTWARE
The main advantage of Quantum software is the quality of underlying
physical
models. Most of competing approaches use different kinds of fragment
based
descriptors to calculate the molecular properties from known
properties of
similar compounds (QSAR). Such models rely heavily on additivity of
molecular
properties, are often overparametrized and lack direct physical
justification. As a result, the prediction power of the models may be
very
good for structures similar to those used in the training set and may
not be
sufficient for absolutely novel compounds. Quantum derives molecular
properties from first principles based models directly using advanced
quantum
mechanical analysis of molecular interactions and thermodynamics.
As a consequence, Quantum ?has much more ?predictive power than its
competition,
but, at the same time, are being licensed on the reasonable terms. It
is fast
and reliable, has an easy to use interface.
TRY ON-LINE DEMO
You can find more information and try on-line Demo version now. You
don't need
any registration. Simply load you molecule and calculate LogP values at
http://q-lead.com.
Note that the on-line version is limited in its capabilities.
PRICING SOFTWARE
Log P CALCULATOR:
* Single user one year license -US$650.
* Perpetual single user license - US$1950.
* Multiple one year license - US$1300.
* Perpetual multiple license - US$3900.
PRICING: SERVICES
Using of Quantum software is a great way to characterize compound
collections.
It also helps you to select structures for future synthesis. We can
perform the
LogP calculations using our own datacenter and feed the results into
your
databases. For 500 thousand substances it will cost about $3000-
$5000 depending
on the complexity of the provided compounds.
Please feel free to contact me should you have any questions, or wish to
purchase a license, I look forward to hearing from you.
Kindest Regards,
Maxim Kholin
Director Business Development
Quantum Pharmaceuticals
+7(495) 156 156 1
Maxim.Kholin.at.q-pharm.com
www.q-lead.com
www.q-pharm.com
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Dear Sir,
Currently we are using GastroPlus software for the absorption
simulation to predict IVIVC, are there any other advanced softwares
available for these kind of studies?.
Thank You,
Viba S, Ph. D
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Dear Dr. Viba S,
I reviewed oral absorption modeling methods and published in
Chinese. If you want absorption simulation to predict IVIVC, maybe
you have no choice but GastroPlus now. There are several
methodologies on this topic, but they are not products. You should
code by yourself.
From my personal viewpoint, because the other methodologies
are similar with GastroPlus (They are all based on compartment
assumption), so they are on same level. There are some different
models, for e.g. to assume that intestine is a tube. They are good to
predict oral absorption according to the literatures, but they are
not good to study IVIVC because they are too complex.
Best regards,
Ma Guangli
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Dear Maxim Kholin,
Your post claims the "next generation of logP predictions" and
further claims that "Quantum has much more predictive power than its
competition".
These claims appear to be unwarranted.
The only independent comparison of multiple logP prediction programs
that I have seen was published in 2003 by Dr. John Dearden of
Bournemouth University in Liverpool, England. ADMET Predictor(tm)
from Simulations Plus was ranked #1.
The RMSE/MAE errors for S+logP (Simulations Plus logP) are 0.36/0.27
with 2D structures as inputs, and 0.33/0.25 with 3D structures (based
on over 10,000 compounds).
Your post indicates that the "accuracy of the calculations" for
Quantum is 0.7 (RMSE, MAE, or what?). You do not report the size of
the data set or whether a completely independent external test set
was used for model validation. All ADMET Predictor models use
independent external test sets rather than leave-n-out methods.
We would agree that additive fragment-based approaches are not ideal.
By the way, in a more recent study (Expert Opin. Drug Discov. (1)1
2006), Dr. Dearden compared logS predictions (solubility) with a more
challenging data set. Once again, ADMET Predictor was ranked #1 over
all competitors.
Simulations Plus did not sponsor or fund any portion of this work
(nor, as far as I know, did any of the other companies).
Best regards,
Walt Woltosz
Chairman & CEO
Simulations Plus, Inc. (AMEX: SLP)
42505 10th Street West
Lancaster, CA 93534-7059
U.S.A.
http://www.simulations-plus.com
Phone: (661) 723-7723
FAX: (661) 723-5524
E-mail: walt.at.simulations-plus.com
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Viba,
You asked for alternatives for GastroPlus for absorption simulation.
This is clearly PK-Sim (R) which can be customized from being only a
module simulating oral absorption up to a fully integrated whole body
PBPK software. Please have a look on our website http://www.pk-
sim.com for more details.
Best Regards
Walter Schmitt
--
Bayer Technology Services GmbH
PT-AS-SB
Monheim, 6550
Tel.: +49 2173 38 4546
Fax: +49 2173 38 9694546
E-Mail: walter.schmitt.at.bayertechnology.com
Internet : http://www.bayertechnology.com
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Dear Walter Schmitt,
Hi, very glad to meet you here. I really read two papers from
Bayer tech. It is a tube model published on J Med Chem. I am very
interested about this model, but I could not implement it. I found
that the function on the paper was divided by a 0. I sent email to
the author 2 times, but there is no any reply. Maybe the email server
lost my email......
May I know whether this model is implemented in PK-Sim? I am
very interested about this.
Best regards
Ma Guangli
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