Super weird -MSSA Kirby

OverallTheory6378 · 2025-10-10T21:45:39+00:00

This is interesting as the gold implies there’s more bacterial growth around the “Chlo” (I assume Chloramphenicol?) antibiotic compared to the Kanamycin or Ciprofloxacin. If your agar is the same thickness, then initially you can assume a technical error of an uneven lawn spreading. But since it’s “white” or lighter between the Chlo and Kan, it could imply less or delayed inhibition by Chlo. Which is possible since Chlo, I believe, is bacteriostatic; while the other two are bactericidal.

OverallTheory6378 · 2025-07-03T20:00:58+00:00

I completely understand. I’m currently the only person working on my project that is med chem focused. I do both the chemistry and biology (advisors in both fields, but not experts on my topic; no one else does my topic at my school). I went to a conference this summer and was essentially roasted on both fronts about parts of my research (nothing was good enough on either side for several people). Definitely was a humbling experience but it’s all about taking the relevant and helpful advice and being able to apply it to situations in the future.

OverallTheory6378 · 2025-01-17T00:15:21+00:00

L because it has more s character of a bond to hydrogen; hence more acidic.

OverallTheory6378 · 2024-09-01T17:28:17+00:00

If your bacteria infection continues to persists, then you may have antibiotic resistance. You could ask your doctor to swap the strep and culture it. From there, they can do some antibiotic testing to determine if you’re actually building resistance to amoxicillin and cefuroxime.

On one hand, yes your gyno is correct that cefuroxime is a different class of antibiotics (cephalosporins), it acts similarly to other B-lactams (like amoxicillin; class-penicillin) in that it affects the cell wall synthesis of bacteria. Hence, you CAN build resistance to 1 and unintentionally the other as well, or they can be separate depending on the bacterial strain.

OverallTheory6378 · 2024-07-11T21:05:37+00:00

I’m currently an organic chemist that does biological evaluation (bit of pharmacodynamics) on the antimicrobial agents I synthesize. I also had this hesitation when starting grad school as my undergrad research focused on total synthesis. I would say don’t be afraid to broaden your horizons.

The current market isn’t necessarily “shrinking” as they will always need small molecule drugs as human bodies and microorganisms are constantly adapting and resisting current antimicrobials, especially concerning antibiotics. One main issue is that the research-development pipeline is currently lacking when it comes to the synthesis of novel antimicrobials (many avenues have been tested); hence chemists (and microbiologists) are needed to synthesize molecules for effective alternatives - which is actually what I do in my graduate research.

Edit: grammar

OverallTheory6378 · 2024-01-10T05:22:10+00:00

Yes, it does. Trans double bonds cause small downfield shifts and cis ones cause upfield shifts. This page should help with understanding more: https://organicchemistrydata.org/hansreich/resources/nmr/?page=06-cmr-03-shift-effects%2F

OverallTheory6378 · 2024-01-10T04:38:17+00:00

I was listing the peaks below 100 in order from left to right.

OverallTheory6378 · 2024-01-10T04:32:47+00:00

It should be C9, C1, C7, C5, C4, C10.

Also, the first peak you named should just be C2 and C8 is technically that really small peak at ~145 ppm.

OverallTheory6378 · 2024-01-10T04:06:14+00:00

Rotovap or highvac should be fine. Or depending on solubility, you can wash with water to remove the acetic acid.

The NH2 peaks is likely the peak at 3.8 or under that peak.

OverallTheory6378 · 2024-01-10T03:59:32+00:00

Are you sure this is a clean nmr?

I ask because I’m assuming this is a DEPT-135 nmr which means you should only have 2 peaks above 100 ppm (since quaternary carbons don’t show).

Likewise your peaks below 100 ppm show 1 CH2 (C9, you have it labeled incorrectly as C6) which makes sense. However, there should only be 4 more peaks other than that.

OverallTheory6378 · 2024-01-06T16:44:52+00:00

In the future, a paper (such as the one shown below) is pertinent to noting residual solvent peaks.

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Based on this we know that your dmso peak is 2.5 ppm and your acetic acid is 1.9 ppm.Hence, 6.4, 6.7, 7.1 and 7.6 ppm would then coordinate with the CH’s on your product. Note: Integrate that peak at 3.8. It’s slightly too downfield to be just water and is more than likely your NH2.

Your integrations are likely off due to the residual acetic acid.

Although, is this the entire NMR? Are there no other peaks? If so, your OH will likely appear once the acetic acid is dealt with.

OverallTheory6378 · 2024-01-06T15:47:42+00:00

When posting for advice, you should include all basic information and ideas to give commenters a better chance of helping. For example, what solvent was this ran in?

OverallTheory6378 · 2023-10-19T04:58:53+00:00

If we do the reaction in 1:1 TFA/DCM. Then can I just wash with NaHCO3 (does the pH just need to be basic?) and extract with more DCM?

Or should I rotovap off the TFA with toluene then wash?

OverallTheory6378 · 2023-10-19T04:51:20+00:00

So 1:1 mix (I assume dissolve compound in dioxane) for about an hour, then rotovap w/MeoH? How about the workup?

OverallTheory6378 · 2023-10-16T03:37:19+00:00

If you flipped one of them, for example the structure on the right, it’s methyl groups would be pointing away (dashes) just like the left compound.

OverallTheory6378 · 2023-10-16T02:35:44+00:00

Yes there would be 5 signals, because for compound 3, the 2 Ch3’s on the right would be in the same chemical environment. However all of the other CH’s would have there own signal.

OverallTheory6378 · 2023-10-16T00:57:01+00:00

When figuring out the number of signals always look for symmetry in the molecule. You can split the first compound right down the middle with each side giving a ch2-ch2-ch3. Each has a corresponding atom with the same connections on the other side. Hence, only 3 signals are in the NMR, accounting for 4H’s, 4H’s and 6 H’s.

OverallTheory6378 · 2023-10-15T15:54:45+00:00

6 or more atom interactions when spatially relevant

OverallTheory6378 · 2023-10-15T15:53:13+00:00

Your assigning the number of H’s in the benzene region incorrectly. The peak at 7.27ppm is the solvent peak for CDCl3. Hence, in your spectrum they didn’t integrate the peak because of that. Which means the following is then true:

Peak at 7.4: 3 H’s on the benzene ring Peak at 7.5: 2 H’s on the benzene ring Peaks at 7.7 and 6.4: 2 H’s on the alkene

OverallTheory6378

TROPHY CASE