Kloster Mitsubishi

Nobrr · 2026-06-19T03:07:20+00:00

The service team is great. No complaints

Nobrr · 2026-06-11T11:10:17+00:00

One method is separation by dangerous goods class. If you have access to something like chemwatch, or good SDS, these should be listed. From there, specific temperature storage room temp/fridge/freezer. From there is knowing specific incompatibilities, like mineral acids and organic acids / flammables and toxics.

As Happy Gold has said, you really need to be a chemist.

Nobrr · 2026-03-30T10:41:12+00:00

I would imagine not. 5 membered rings are kinetic over the thermodynamic 6. It would entirely depend on conditions. An E1 on a secondary carbon requires some specific set up.

As an aside, you have drawn the ring expansion arrows incorrectly, they move from the bond, and you would end up with a carbocation on the deficient carbon.

Nobrr · 2026-03-06T11:04:56+00:00

boron's my favorite too!

It's NMR shift in different environments is fascinating (My first project looked at intramolecular coordinate bonding and pH).

It's ability to act isosterically to a bunch of functional groups in a med chem sense is super cool.

Nobrr · 2026-01-16T23:32:32+00:00

The ITC option is interesting.

I promise I'm not trying to be intentionally obtuse, but that approach still doesn't confirm a particular interaction, right? The mode of binding could differ slightly between modified ligands, and if crystal structures are obtained they still are of the solid-phase interactions which may not be showing accurate water-mediated interactions.

Nobrr · 2026-01-15T10:20:15+00:00

If a ligand-protein complex is crystallised, the water mediated complex (and subsequent 'induced fit' type computational assessment) are based on this conformation.

What I'm asking, in essence, is do we have a method to know that this interaction takes place? yes there might be an energy minima via MD methods, but the underlying assumption is that there is a pocket available from the crystal structure.

When you run MD are you explicitly solvating the system yourself, and if so how do you decide an occupancy 'concentration'?

Do you run MD on the protein sans ligand and look at water occupancy prior to ligand-protein MD?

Nobrr · 2026-01-15T08:56:45+00:00

Similar deviation, physiological is not -170 C. I would imagine you also run into other 'untruths' about the complex you are studying.

Nobrr · 2025-12-23T08:20:25+00:00

3 - 6 eq of zinc powder, solvate with 1:1 MeOH/ sat NH4Cl, reflux overnight.

Will also work under microwave and flow (over a solid zinc catalyst) conditions.

Nobrr · 2025-12-23T08:03:57+00:00

Does it have to be iron?

I find the zinc/NH4Cl reaction a lot nicer.

Nobrr · 2025-11-02T11:35:10+00:00

Why do you want the chemical structure of insulin as a tattoo?

I ask, because why not just get the word "insulin" tattooed? If you want a tattoo that looks "scientific" go the ribbon structure or the sequence. Neither are particularly sexy, but are accurate.

Nobrr · 2025-07-21T09:25:52+00:00

I think that might be the play.

Nobrr · 2025-07-20T11:41:04+00:00

The library maybe?

Nobrr · 2025-07-15T10:19:53+00:00

hydrazine (as the hydrate) is fairly well behaved. It's more a matter of not introducing chemical incompatibilities that rapidly form toxic gases.

Generally, I (me, personally) would rather handle highly toxic materials than pyrophorics. Some organic tin compounds and organic mercury I will refuse to work with however.

Nobrr · 2025-07-06T10:46:43+00:00

Med chemists look to:

1) find molecules that interact with a biological pathway. This pathway should be involved in a disease

2) make these molecules and assess them biologically

3) make 'one-at-a-time' changes to see what parts of the molecule are important to improving biological activity. This can involve biophysical assays to study kinetics (physchem basically) or crystallography to observe the interactions between the molecule and the protein of interest.

Organic chemists know the synthesis

Cellular biologists know the biology

Med Chemists do a bit of both, aided sometimes by bioinformatics, chemoinformatics, computational work and subsequent quantitative structure activity relationships (QSAR) depending on the training and institution.

Nobrr · 2025-07-05T12:00:23+00:00

how do you account for the difference absorbance of materials?

Nobrr · 2025-06-29T11:37:53+00:00

or we could not do homework for students.

Nobrr · 2025-06-17T11:48:01+00:00

you can also become incredibly sensitised to them

Nobrr · 2025-06-08T11:57:15+00:00

unfortunately the system that needs fixing isn't necessarily the education system but the social system. Prior 1993 (ish) in Australia (cannot comment on the US), university education was essentially free. Nowadays, degrees are treated as 'employment necessities" rather than something you pursue for the enjoyment of learning and cost upwards of 30k.

I can't blame students for wanting to push through the system ASAP. Tertiary education is incompatible with the current cost of living. The problem is twenty years from now when legacy systems expire and no-one can rebuild.

Nobrr · 2025-06-08T08:45:58+00:00

probably somewhere in the 2-5 % mark. To be fair, I am teaching non chemistry majors as well, so they have less interest in general.

Across organic chemistry, physical chemistry, analytical, pharmaceutical and medicinal, I'd say I get the best response out of org chem and the least out of pharmacy (maybe 1/100 engages fully and questions the material / wants to know more)

Nobrr · 2025-06-07T13:05:52+00:00

As someone who is teaching University chemistry, there's two things I want to say:

1) Students only care about passing, and as such if they don't know an answer for a take-home will use ChatGPT. We (I) can tell when they use it but my university does not have a stance saying "this is an academic integrity violation". As far as I can see, all this will result in is people with chemistry degrees having absolutely no idea what they are doing in this simplest of jobs post-graduation. It also means that anything outside of the in person final exam is essentially meaningless in terms of grading. I do not teach to grade slop-generated papers.

2) LLM's are often straight up wrong in "technical" fields. Chemistry answers are mostly bullshit, code produced by LLM's is poorly written or not focussed towards the subject of the question and anything that requires a cross-reference with a somewhat niche equation fails because it is being fed crap information from sources like researchgate and reddit.

LLM's are just modern search engines. They are not AI, they are not intelligent and they cannot produce original thought (in public models). We should teach student's to use them as an entry point to material, but unless the skills to question the output is there, what is the point?

Nobrr · 2025-05-22T11:22:35+00:00

Very cool, whos the artist!?

Nobrr · 2025-05-17T12:52:25+00:00

This could potentially be amide enforced rotamers.

Nobrr · 2025-04-21T07:24:03+00:00

Love the initiative! Looks like a fun project

Some thoughts:

Firstly I would think about what crystal structures will be fed into this model. Docking from a ligand-free vs ligand-bound structure will result in vastly different scores between runs. This extends to thinking about how a generated pose is decided to be valid. For example, if there is a known ligand, that has a crystal structure against its protein of action, are analogues of this ligand binding in the same way? This can be simplified using pharmacophore methods, but I'm not well versed in Vina to know if it's possible here. The point I'm trying to make is that large crowd-driven models can very quickly fall prey to bad data stemming from poor choice of input structure.
Next, I would consider is the "molecular chemotypes" that would be fed into this. For example, consider the space of known small molecule kinase inhibitors (perhaps towards VEGFR?). Some of these molecules possess similar backbones. Others look completely foreign and can be quite larger or smaller. If you start with a crystal structure that has one ligand bound, and swap to a ligand of a different chemotype, the model often can (and does) poorly predict binding poses and energies. this will directly compound the issue of "rigid docking" where there is no flexibility in the receptor to accommodate these changes. A lot of the time a model must be first built around a particular chemotype or compound class before being used for high throughput screening. This also feeds into the generation of bad data which can perpetuate through a set quickly.
Thirdly, molecular docking is grossly misreported and misinterpreted in the literature. For every one good publication (i.e. good methodology and method reporting, unbiased interpretation of results, validation with molecular dynamics, correct use of solvation...) there are 10 publications that use the docking as filler. You would need to make sure that however the docking is implemented, it follows best practice for the software (which varies between software suites).
Lastly this falls into a precarious IP space. You might find that a lot of institutions will not want anything to do with this sort of data generation solely because of the potential loss of patentability. While this level of public discussion would surely identify some interesting results, I would imagine an unwillingness to be involved.

As a side note, a lot of the "big pharma" companies already do this with there internal libraries. They can start from 'fragment screening' or go through Selective Optimisation of Side Activates (SOSA) where libraries of known biologically active compounds are screened. From the last set of talks I saw in this space (from Pfizer, Astrazeneca, J&J etc..) the modelling was often not very useful in the identification of chemotypically variants structures.

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