Showing posts with label CAS. Show all posts
Showing posts with label CAS. Show all posts

Thursday, May 5, 2016

Two Billion Compounds?

I've been cracking my skull against a peculiar problem this week:
How many unique molecules compounds have ever been made?*

I'm referring to those produced by humankind, over the past 250 years - give or take a decade - of formal chemistry effort. CAS claims 100 million molecules in their collection, and predict, at the current rate of registration, another 650 million over the next 50 years.

Berries by the side of the road, 2016.
Not counted in billions.
Certainly other databases exist, a well-curated larger example being ChemSpider (34 million), but I'm sure the Venn diagram for that against CAS overlaps quite a bit. Ditto PubChem, which according to ChemConnector had over 37 million structures in 2009, but lots of errors, duplicates, and isotopomers, to hear him tell it. Outside the med-chem arena, there are exciting new collections such as the Aspuru-Guzik lab's Clean Energy Project, to identify photovoltaic materials. Surely the assembled collection of privately-held corporate data from all chemistry, pharma, biotech, and engineering firms must include another windfall; ~200 million compounds?

So, let's try a thought exercise - say we limit the set of what we call "made," or synthesized. We won't consider polymers, whether natural (DNA, polysaccharides) or artificial (Teflon, urethanes). Screening collections, libraries, and combinatorics; unless someone produced >1 mg, I'm leaving it out. Metal complexes and salts are in, since most of the time inorganic and formulations colleagues still produce quantities you can hold and measure (and get a melting point on!).

Granted, by referring explicitly to the public and private chemistry databases, I'm not including dark reactions, those failed experiments or perhaps non-optimal yields that never make it to publication. Based on my lab career (and that of my hood-mates), I'd say there's a comfortable 5-10 molecules made for every 1 that gets reported somewhere. Of course, since many of those are literature preps or repeat reactions, I don't think it inflates the count that much; truly, novel molecules tend to creep into papers and patents somehow.

Chemical space gurus, I apologize - I only want to count things that have been bottled, columned, purified, and analyzed. Large computational data sets of billions - unless they've been made and characterized - aren't up for consideration. Neither are metabolites isolated from plants or microbes; no fair counting what we relied on other organisms to make. S'posing this means we also leave out decomposition products and geological materials.

So them's the rules: 1 mg produced and characterized, non-polymeric, must have been made or produced with human hands. Salts and metals are in, along with isotopomers and stereoisomers.

What do readers and commenters think? My guess is in the title of this post.

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*On the Twitter, Peter Kenny points out that I should, in truth, be asking after compounds, not molecules. Fair enough.
** Another reader points out that ZINC15, the database of "stuff you can buy now," only includes ~10M at present.

Sunday, July 20, 2014

Review: ChemBioDraw 14.0

Dear ChemBioDraw* Ultra 13.0,

Listen, we had a good run together. But I've fallen for another: ChemBioDraw Ultra 14.

My good friends at PerkinElmer (PKI) were kind enough to grant me trial access to their spiffy new chemistry drawing software. As an avid user since, oh, say, ChemDraw Pro 4.5, I feel confident in stating that this version wins all around for smoother operation, better templates, easier file export, and better shortcut keys.

So, I figured what PKI really wanted me to do most was to try and BREAK ChemBioDraw 14.0
 . . .if I could. Did I succeed? Let's talk a walk through the software and find out.

CBD 14.0 means NEVER seeing this screen again (hooray!)
Starting at the top, I figured I'd check the "What's New?" link in the help menu. One thing I appreciated more than I thought? ChemBioDraw 14.0 directing "Help" queries into the appropriate section of the User Guide. Version 13 still spawned its help window inside Windows help, with the infamous purple booklets leading you down wild goose chases of clunkily-presented information.

Drawing hasn't changed much since 13.0. At least the text direction auto-correct -- which drove me batty in former iterations -- seems to have been tweaked; the system now opens my older drawings the way I typed 'em in originally (hence, below, attaching pasta sauce to a scaffold in place of a sugary placeholder).

I promise this made sense in earlier ChemDraw versions...

The CBD 14.0-to-SciFinder jump works much more smoothly than I had anticipated. For those of us who shuddered through dial-up desktop versions of SciFinder in the late '90s, this version feels like the sleek Lamborghini of the search world. After drawing (or importing) my structures of choice, I lassoed them up and pressed the little "SciFinder diamond" on the top toolbar. Within about 5 seconds, a new window opened with the standard exact / substructure motif. Two clicks later, I'd be deep into the primary literature.

So, my goal was to break the system, right? Here's a logical place to try - I attempted to load each and every complex structure I had drawn since starting my fledgling blogger's career, around 2009 or thereabouts. Again, I was amazed by the speed and accuracy of the SciFinder pop-out, which returned roughly 90% of the correct molecules I'd searched for (below):

From this 2011 post
From this 2013 post
From this 2014 post
However, it's not all bubbles and sunshine. Two of my molecular queries bore no fruit**; perhaps they're too new to have been uploaded into CAS's databases yet. But one thing remains tricky: drawing and searching for metallocenes. Along with their new push into biology clip art, ChemBioDraw has a renewed focus on making sure you've got those sandwich compounds properly aligned.

Sigh. If only I remembered what they were all supposed to be...


Now, even after aligning my query using the proper template, SciFinder makes a mess out of it.

From this 2012 post

So, obviously I went looking for things to break, and found some rather limited examples. Honestly? The rest of the program works pretty well. And writing this review gave me a wonderful opportunity to poke and prod at the product in ways I hadn't in far too long.*** I finally realized you could change the solvent on the NMR predictor! I played around with expanding and collapsing peptide and RNA strings. And the post-drawing mods to more complex peptides, like disulfide and lactam cross-linking? Much better.

Found on p. 126 of the User Guide. (Get it?)
I'd like to shake the hand of the person who slipped this in...
R.I.P., Optimizing Octopus

I will take this final moment to remember a long-lost piece of ChemDraw lore. Once upon a time, to "clean up" one's structures, the icon looked something like this (right). I've heard it referred to as a jellyfish, a squid, a broom (no!), but I always knew it as a friendly little octopus. With CBD 14, any doubt about its brushiness has been cast aside with a full-out icon redesign.


Looks great, guys. Now let me think about more ways to use it for actual work!

Thanks again to Philip Skinner and PerkinElmer for the chance to review the software.
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*For other blog reviews of ChemDraw products, see Jess The Chemist, Andre the Chemist (no relation), or Chemjobber.

**Here's the structures that returned empty SciFinder searches. Both compounds (left, right) were first reported in 2014.



***P.S. I never knew you openly solicited beta testers for these products...gimme a call sometime, PKI!

Friday, January 18, 2013

Friday Fun: WWWTP? CAS Stock Photo

OK, Chemical Abstracts Service, here's where I get stabby...

c. 2012, Chemical Abstracts Service

I clipped this well-meaning low-res stock photo out of a SciFinder help page. First off, what's with the incomplete PPE? Don't you suppose this enthusiastic young lady analyzes (urine?) whilst wearing gloves? She looks like she's selling glassware, BTW...I've never shown off my products quite like that.

And who are the MBA-types posing on the periphery? If they're admiring the benchwork, they should have goggles at the least! Methinks this may have been photoshopped from a med school recruiting website, perhaps?

CAS, you're part of the largest scientific society on the planet. How's about an accurate picture?

Thanks,
SAO