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Pseudohalides (and thiocyanate/rhodanide especially) physiologically acceptable

Limpet_Chicken

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Title says much of it.

Is thiocyanate, or cyanate for that matter a physiologically safe moiety in the case of an aliphatic terminal functionality?

Basically, I am looking for electron-withdrawing substituents isoelectronic with halides. Ones that can be made to serve the purpose of a bioisostere of a halogen, to be used as the terminal group on thiazolylethanol but without the obvious propensity to alkylate the user. This is an extension of my chlormethiazole thread.

So far, come up with: nitro (oxidatively a bit icky but not an alkylator, and hey we eat nitrate and nitrite all the time, in the form of cured meats), thiocyanato, isocyanide but I'm NOT going there, fuck no. Thiazolylethanol stinks enough as a sulfurous fuckup from the pit, without EATING a fucking isocyanide. I won't even work with isocyanides in the house, strictly OUTSIDE chemistry if at all, ever. I hate 'em. The stench is indescribable. Cyanate, thiocyanate. Iso(thio)cyanates are out, terminally reactive. Azides are out, as are fulminates, toxic as hell. Cyanidesque, if thats a word. Well if it wasn't it is now=D Isocyanides don't USUALLY share in the cyanides' toxicities but however they smell utterly foul. Not talking ammonium or hydrogen sulfide foul, or even alkyl selenol foul, just...hideous, uniquely, unutterably, indescribably abominable. Like a dead rat from tartarus that crawled up a rotting badger's ass and died in hell. Covered in satan's own shit.


Read about aluminium polyatomic supra-molecular pseudoatoms, that in the case of certain aluminium cluster sizes, behave stably, and mimic halogens in their reactions. Could these be tacked onto an alkyl or aryl carbon backbone? I mean is it even physically possible to do so, by any means at all, not involving atomic manipulations of the physical kind and producing tiny quantities only?
 
Read about aluminium polyatomic supra-molecular pseudoatoms, that in the case of certain aluminium cluster sizes, behave stably, and mimic halogens in their reactions. Could these be tacked onto an alkyl or aryl carbon backbone? I mean is it even physically possible to do so, by any means at all, not involving atomic manipulations of the physical kind and producing tiny quantities only?

Atomic clusters are a thing that I've actually researched when I was working in a physical chemistry lab... The aluminum cluster that behaves like a halogen is Al13, and it has a high tendency to accept one electron and form the very stable Al13- ion. Here's a computational chemistry article that's about quantum chemical calculations related to the hypothetical SN2 reaction between methyl iodide and Al13- to form CH3Al13: https://www.researchgate.net/figure...heme1-SN2-type-reaction-for-Al-CH3I-Al13CH3-I . I hope you can access the full text. In that study they reached a conclusion that this reaction is very unlikely to happen. There probably is some way to create such compounds, but I'm not sure how stable they would be.

If you're thinking about something like replacing the bromine atom in 2C-B with that aluminum cluster, I'd like to point out that I would personally prefer not to ingest anything that contains aluminum and crosses the BBB...
 
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Well you got the general idea of my line of thinking. Although it was the thought of further modifications past bromo for the chlorine in chlormethiazole and Br in...err..bromethiazole. Because I don't fancy putting the iodine or fluorinated analogs in my mouth (or up my ass for that matter). Iodine is too good a leaving group, I don't want to thiazolylethyl-ate my GABAa receptors' barb sites. Or anywhere else for that matter.

But wondering what else to do with that thiazolethanol really. The alcohol itself appears to be active, to a lesser degree than chlormethiazole, although it stinks like satan's foetid dysentery-squirtings, and the thought of trying to take the stuff orally is about as tempting as downing a yard of cold badger sick, fermented into beer via the action of yeast chunks gouged off of cherie bliar's (spelling intentional;)) greasy, oozing vaginal toadstools, delicately flavored with the jizm of a rusty mink.
 
What's the actual reason for fluoro not being acceptable? Also what about TFM, or using other heterocyclic groups like oxazole (yay no sulfur = win?) or oxathiolane? But maybe such options are limited if B1 imposes the restrictions?

I like the pustular poetry ^ and also the mental image of contracting 13-fold Alzheimer's. But I have no idea about the thiocyanate or permutations of it... you apparently answered that yourself quite quickly.
 
Well its isothiocyanate or isocyanates that are highly reactive with -OH groups. Thiocyanate and cyanate do not share that same property. But thats in the case of ionic cyanate/thiocyanate salts, I am unsure weather or not aliphatic or aryl cyanate/thiocyanates are acceptable in vivo. Hence my asking.

Fluoro, just because its on a 2-carbon backbone, and at least in some cases, like the various nasty as hell looking synthetic CB1 agonists that have of recent times ended up on the consumer market, can be metabolized to fluoroacetate.
Already thought of the option of 1,1,1-trifluoromethyl, that does intrigue me probably most of all out of the easy options.

As for oxazole etc. yes that appeals, as chlormethiazole itself can end up in sufficient quantities taken long enough in the setting of recreational binging, as some truly heinously stinky sulfurous muck. NOT very nice when its coming out in your nasal fluid and your saliva!

I'd like to explore other heterocycles than thiazolylethyl, and whilst yes, the lab is not a uni or workplace one (in the sense of somewhere I wake up at 9am, have breakfast, take a shit, have a smoke and leave out of the front door to travel thereto) but it is, and without meaning at all to be boastful (not to say I'm not proud of it immensely, I am, but not without some justification), it is a lot more sophisticated than the kitchen chemistry type stuff some engage in, doing the likes of DMT extractions,
ephedrine/pseudo LWRs and the like. So its realistic to want to have a crack at the other heterocyclic options, even if I do have to do it from scratch. But it makes sense does it not, to exhaust first, the options which are quick and simple and easy and cheap to explore, before going to the effort of having to prepare the various other ring structures? that is to say, its a lot less effort to just buy a bunch of thiamine, crack it and separate the useful half from the pyrimidine byproduct with simple cold water washes, recrystallization, and then a one step (or more if the Appel rxn be used instead of the classically used reagent for E.g introducing the traditionally added halogen atom [I'll say no more than that, anyone who wants to know won't have much difficulty in finding that information out there on the web for themselves without my help] to the end product, barring workup.

Its not that B1 is a restriction, quite the opposite, its a readily available well nigh perfect starting point, so naturally the thiamine-derived options get explored first. Not laziness, just expediency. And I'm all for seeing my work come to fruition nice and quick and clean, the sooner to reap the reward at the end:)
 
I see.. well if uneven C number aliphatic sidechains are alright as opposed to even ones (which could get chomped up by enzyme cleavage to fluoroacetic acid), 3-fluoropropyl could be an option..

For all I know simple nitriles should be mostly safe, being largely unmetabolized..
(Something like PCC is different though, undergoing SN2 reactions with the pip?)

It definitely didn't sound as if you were running a soup kitchen.
 
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Yeah I had mentally listed nitrile under such substituents and largely discarded the idea for the same reason you suggested it actually, namely that 'should be' 'mostly safe' and 'largely' unmetabolized, are relative when its something quite so cyanidesque in character.

Anyone know how steric bulk close to the halide, of the alkyl chain affects the character, as long as the electronegative substituent on the alkyl chain is able to get into position to bind with its target, or how chlormethiazole actually overlays with GABAaRs once bound, in the in-vivo context? and chain length itself? can anybody elaborate upon the effects of simply lengthening the aliphatic chain of chlormethiazole itself, either doing so and retaining the EWG in its original place relative to the end of the aliphatic chain and the origin point of the chain-EWG relative to the end/beginning of the thiazole ring itself, (that is, 2-chloropropyl vs 3-chloropropyl, and the distance between the terminal carbon of the thiazole heterocycle and the electronegative substituent? chloro is probably the most likely well known if anyone has actually bothered to take a proper look at the SAR. Its not like chlormethiazole itself is either a modern drug, or one which HAS any other relatives in clinical use anywhere that I know of. IMO the only reason its still around at all, is that unique additional property, for a sedative-hypnotic/anticonvulsant of its inhibiting alcohol dehydrogenase, which makes it especially desirable in alcohol detox as it helps prevent the abrupt drop-off of blood alcohol levels in in-patient alcohol detox, from whatever the pisspots so treated have left in their tanks when they are admitted.

Its a borderline antique of a drug with some funky physical properties (like the melting plastic for example, although its not all that well known amongst modern pharmacists at least not here where I live. I had to ask the pharmacist that dispensed some
to me just this monday to take back the plastic bottle he handed me the prescribed number of capsules in, and to give me a glass bottle. He hadn't got a clue why, and gave me a funny look at first, as though I was being a fussy pain in the arsehole, but then was quite alright about it after I explained quite how aggressive the stuff is and that it should only ever be dispensed in glass containers. Had to point out that a formerly used computer keyboard of mine ended up with two heminevrin caps WELDED
to it, and that I eventually, after draining the liquid out carefully, had to remove the remainder with a chisel. And that the first time I ever handled it in bulk, I made the mistake of running (trying to) the pilot quantity in a plastic container. It ended up as a blob of funky smelling goo. Not as fast as pouring acetone onto polystyrene foam, but the end result was of a similar nature.

That, the fact of its being a certifiable fuckweasel to try and form proper salts of the stuff, and its being a barbiturate binding site ligand rather than benzo-like or like those rotten fucking modern Z-drugs, and like the barbs, similarly steep dose-response curve and lethality in overdose. Presumably untreatable by flumazenil also, given it doesn't bind like a benzo. If it weren't for the fact that its about as easy as GHB to go from starting compound to end compound then I would count myself intensely grateful for that alcoholic detox use. I'm not one, and am unlikely ever to be (he says with a bottle of beer on the way to his lips, ahaha!=D), but that must be what keeps good ol' heminevrin still in the BNF.

As we all know how much the medical community wanted barbiturates gone, aside from pheno and butalbital, other than for surgical anaesthesia.


Quote (solipsis)-''it definitely didn't sound as though you were running a soup kitchen.''

Hm...anyone else hear that strange noise? the one that sounded kind of like 'sgnnarrkkhoorrfkhkhkhkhkhngghaaa'?
No? just me then? well me and the neighbors. thats the sound of me inhaling in reverse. Out of my tear glands, ear canals and nose. Sideways. And narrowly managing to prevent the sofa and my laptop from being hosed down with beer.
Be a gent, and PM me your home address and post-code. That way if I find the door kicked in by several burly arseholes in white coats wielding a leash on a long stick and dart guns loaded with thorazine, I know where to mail the bag of flaming dog muck so it won't end up delivered to some poor person entirely innocent of having sent one cackling, beer-spewing at-face-value-and-first-impression rabid maniacal fruitbin (but in reality quite sane and well adjusted, its everybody else thats lost the plot autie terminal addict of all things alchymycal and biotech) to some shithole full of insane people doing the haldol dance to music that only they can hear.


And you really cannot possibly begin to imagine how much I wished that the damn USB drivers for this computer fucking worked, because I was about to do a short videoclip of cup-a-soup being prepared in a 2-neck RBF,thermometer in the side, and the
boiling water coming in from one of my sep funnels, mixing by means of the mag stirrer on one of the hotplates=D

While not entirely unamusing nevertheless, a mere description falls far short of the amusement value that would have had were there a point to doing it, with my being able to post the clip. I fucking HATE windows 7. Did I ever get any of this super-difficult-to-fix driver bollocks with XP? no, I did not. Hell plenty of stuff just had to be plugged in and the screws, if any, screwed in and the computer started and there you go, working. Not this fucking POS.

The uneven numbered fluoroalkane thing is based on my extrapolating from the inability of the odd numbered carbon chained analogs of the likes of 1-(5-fluoropentyl)indole or indazole based cannabinoids to end up as fluoroacetate. However one thing that needs to be taken into account is those were terminal haloalkanes, as is of course the 3-fluoropropyl analog of chlormethiazole you suggested, but it does meaning lengthening the sidechain by -C- and pushing that EWG out too.


Anybody handy with the kind of software used to dock a ligand with virtual receptor models and overlay other ligands on top so one an actualy SEE whsts going on, specifically how thry'd behave in vivo in their natural conformational states
 
TLDR

Maybe you could try esterifying the alcohol group (like acetate or carbamate). Maybe it won't work and attack the sulfur instead. I don't know as much about chemistry, so maybe there's a reason that was not brought up.

I think the best change would be to replace the sulfur with oxygen, but I know the synth will probably be harder.

See the oxygen version's LD50 is the same for one administration method:
http://chem.sis.nlm.nih.gov/chemidplus/rn/823-51-8
http://chem.sis.nlm.nih.gov/chemidplus/name/clomethiazole
 
I would go for a cyano group if you want an electronwithdrawing, but not too reactive group. The cyano group is a pseudohalogen.
 
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I'll have to look into the oxazole.

Whilst I would need convincing reasons to believe it safe enough to test the insatiably curious part of me can't but help wondering about the selenazole. The tellurium analog is NOT happening. No way in hell for the same reasons that apply
to tellurium compounds in general. And volatile tellurium compounds aren't things I'd want 'hanging about' so to speak. Never experienced it, but I've read some real horror stories about Te-containing organics.

Concerning the selenazole, bet that doesn't smell too good either, where sulfur is bad, selenium is usually worse. Main concern however would be absorption of too much Se, its quite toxic in quantities above those needed as a dietary nutrient. That said,
Sasha Shulgin made some psychedelic phenethylamines incorporating Se into a heterocyclic ring. Not a priority though IMO. The oxazole does sound interesting, no more toxic (mice mind you, and most certainly, as the phrase goes, I'm a man, not a mouse=D

The idea of a carbamate where the terminal -OH is, or more usually the chlorine, now that actually does rather pique my interest. I'd have to take a look at and compare the general structural themes in that class, but there are quite a few carbamate sedative-hypnotics. I've only had one of them, methocarbamol, and it was absolute shite, and it stank, too. But AFAIK methocarbamol is a pretty much the shit-covered black turd-shaped, crap-eating feces-sheep of the family. Best thing I can compare
it with is a really shitty heap of crap, floating in a lake of diarrhea. One that stank funny, not like feces just, funny and not in the hilarious sense, funny in the 'hey, did somebody stuff a dead rat in the air conditioning' sense of 'funny':p

Didn't do much good either, got scripted it a fair few years ago either for my myoclonus or for the muscle spasms. Can't remember which, not that it matters because it didn't do a damned thing to help with either of those. Some of them do seem to enjoy some popularity however.

On the subject of organic compounds that contain cyano groups how does one figure out if a given substance is possibly capable or likely to release cyanide in vivo.
 
Expect hydrolysis if you have acid reflux :) (get it?)

http://www.ncbi.nlm.nih.gov/pubmed/6128199

It doesn't look too good for even aliphatic nitriles, metabolism in the liver microsomes yields cyanide (or at least typical cyanide poisoning symptoms) - wiki seems to be wrong about suggesting nitriles to be sort of fine, even if the cyanide liberation is not complete.

I generally like fluoro analogues.. :) it's a pseudopseudohalogen..
 
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*skhnoorrfhghkh!* acid reflux..good one.

Although acid reflux sucks kitten-microwaving rotting paedophile arses. I suffer from it terribly. To the point where I'm now on at least 7 different meds for it, and those are just the ones I can remember off the top of my head.
So far, theres scopolamine transdermally, the butylbromide quat of same, orally, a PPI, gaviscon, cyclizine, cimetidine and ondansetron. Used to be on ranitidine, but told my doc I wanted it changed to cimetidine so I could take advantage of its cytochrome P450-2D6/P450-3A4 inhibition and get more bang for buck out of my 2 morphine formulations and oxy script. He did do somewhat of a double-take and give me a rather strange look that I don't have in my dictionary of body-language to intelligible meanings so of course couldn't translate, but he did do what I asked him too, to quite considerable success too

Had to add the ondansetron recently too, due to the severity of the vomiting up of torrents of acid, and when theres no more acid-cookies in the bag left to toss, a nasty mixture of foam and bile. Gaviscon helps, when used with the PPIs and all the mountain of other pain-in-my-arsehole-to-remember meds, but only so much, because it in and of itself can cause me quite a bit of discomfort, due to the acidity in there reacting with the amount of base needed to neutralize it resulting in too much gas buildup in my stomach, causing distension, discomfort and on occasion pain. To say nothing of belch after belch after really very impressive indeed belch. Once I pop, so to speak, I just can't stop:p After taking the amount of gaviscon needed when my dyspepsia and reflux starts kicking off badly, it just keeps coming, one after another after another, and theres nothing at all I can do to hold it back, it just comes out, regardless of the company or the setting. You ever watched the TV show 'the simpsons' solipsis? because fuck me diagonally with a rusty mink if it doesn't sound for all the world,exactly like homer's friend barney, the drunkard from moe's tavern, the way he does those long, loud reverberating 'yaarrrkkkkhhhh' kinda burps, that make his tongue stick out and vibrate, like a charging jihadist mujahid, if affected with terminal flatulence in the middle of it's battle-wail=D


Expect hydrolysis? lamentably, I've come to do just that. Only its of my stomach lining and throat. Its put me in hospital several times. More than one of them being traumatic in the worst kind of sense, when the stupid fucking cock-nibbling whorespawned anus licking pigfucking sewer-rat-bastards KNEW full damned well that I am physically dependent upon opiates, not through abuse or even recreational use (well, that too, sure, but thats just a side-dish, so to speak), but through having been put on and maintained on those opiates by my doctor prescribing them, and have been for years, and years, and more fucking years. They knew this, and knew that the scripts were all currently still issued and used, yet denied me all but shitty, utterly worthless doses of oral morphine (10s, 20mgs 12 hour XRs at that! bastards, completely ignoring me when I tried explaining the low oral BA of morphine, and that even at the high doses I am MEANT to be on, I cannot even get close to it being of use without concurrent enzyme inhibition by cimetidine, and preferably grapefruit juice also. Didn't even give me my godsdamned chlormethiazole. I had to rely on a (plastic...ick) measuring syringe stowed away with me in expectation that was going to happen again, and a small RBF of chlormethiazole base, eyeing the dose, as I hadn't my scale with me, and stuffing it up my damn arse in the ward toilets. No antacids, no PPI, not sufficient pain meds even to prevent me going into fullblown withdrawal. I eventually managed to have someone get me some, although still not even close to enough, after telling them they either get off their fucking arses and GET SOME, or I was going to get on the phone/my laptop, and damn well start ringing round/IMing until I found someone who would do me some heroin, and bring it right round and deliver it to my bedside on the fucking ward.

(I am not usually so..well...rude, and don't typically get in people's faces like that and stir up grief. But I won't take being treated like that. Fer' chrissake I was ON that ward because I'd near collapsed due to the acid reflux and vomiting HCl and bile, streaked with blood. Any doctor or nurse is going to know what happens to an opioid dependent patient when they suddenly have their drug or drugs stopped, once the last dose taken wears off. Not least amongst those effects is what? vomiting? noooo...surely fucking well not! There was me thinking it makes the world rain candyfloss and ice cold beer....)

At that my telling them that, they did actually do something, but like I said, not NEARLY enough. Got some oxy out of them, albeit a piss poor offering all the same. And they expected me to take anything they did give me orally too. Despite being able to watch my trying to take a mouthful of water and it going down for less than 30 seconds before shooting back up, and out, again.No, I'm not a rude person, and I don't like to see people rip into nurses, doctors etc. because they are trying to help heal those same people. But I do have my limits, I wouldn't take being treated like that much dog shit from anybody else, so there sure as shit is no special rules in play for the medical profession to be allowed to sit there and do their best to make me fucking miserable, and in doing so, worsen the very problem I was admitted to hospital for in the first place. I don't deserve to be treated like shit either, they don't, of course not, but like fuck do I! Bastards left me like that for a bit over three days, before anything got fucking done. Even tried to get away with refusing me a second tablet of the ondansetron they'd given me, when it simply rocketed back up into the barf bowl. Claimed I couldn't have another one, because they didn't actually witness it come up. Actually implied I'd faked the pill-sized white splatter on the edge of the puke bucket, that I'd swallowed mere seconds before, just because they were not actually in line-of-sight at the time. Again, had to kick off, because no way was I standing for that! not that I could stand mind you, the foetal position was demanding enough!. Did get a shot of the zofran IM though, as they could see I'd go at it all night if I didn't get my way in that particular instance. And I don't think it unjustified/unjustifiable either, not given the situation I was in, and way I'd been being treated in a way that a decent human being would never dream of treating a fucking half-dead rabid dog.

Regarding nitriles and their safety..Yeah, I thought as much. Acetonitrile, whilst it smells good enough, is known to produce toxicity if sufficient exposure occurs. Although it appears to vary a great deal between individual compounds. i think unless I ever get round to in-vitro testing and analysis on the cyano analog of chlormethiazole, I'm going to give it a wide berth, insofar as actually exploring it in vivo. I absolutely refuse to test ANYTHING on animals. Unless its testing the preference for one or other brand of animal chow, that is about the one and only test of any kind on any species that I am willing to tolerate. I don't keep animals in the lab either, unlike me, they can't give or refuse consent to be exposed to anything floating around in the air in there.
 
To Limpy and Solipis, nitriles are harmful if ingested in high enough quantities. Acetonitrile is particularly safe, but for other low alkyl nitriles the dangerous value is in grams. Typical drugs are not ingested in those quantities, but rather in milligrams, maybe tens or hundreds.

Nitriles hydrolyze into the amide, and then into the carboxylic acid in acidic environment, but cyanide ion release means C-C bond breakage, which is not very easy. Nitriles are used as drugs, and I haven't heard of cyanide toxicity resulting from them.

Fluorides are also OK, but their behaviour differs from the other halogens somewhat.
 
Sorry if I missed it in the sea of text but are alkyl trifluoro groups reactive in the body? Like the one in this molecule (an anabolic substance):

240px-LGD-4033.svg.png
 
Organic fluorides are the least reactive of organic halides. C-F bond is the strongest carbon bond. Trifluoromethyl can be considered an unreactive somewhat electronwithdrawing methyl group, because the volume of fluorides is roughly similar to hydrogen.
 
What is more of a problem though, unless I'm mistaken, is that if an alkyl side-chain is cleaved metabolically into segments of 2 carbons, a part with fluoros can end up as something like trifluoroacetic acid. I believe the problem with that is that it can participate in citric acid cycle reactions, but mess with enzymes binding way too long with them, which impedes healthy citric acid cycle perpetuation.
Earlier I forgot about issues with fluoroalkyls because like BD says they aren't really reactive per se, then limpet hinted at fluoroacetic acid problems.. this type of thing was a concern with some synthetic cannabinoids that have fluoropentyl side chains - but being an uneven carbon number this isn't considered as unsafe.. also the potency of such a drug will matter a lot, because if nothing else it is a big factor in determining how much of toxic metabolites can possibly be liberated. Clomethiazole type substances are clearly much less potent than many of those noids.
 
Atomic clusters are a thing that I've actually researched when I was working in a physical chemistry lab... The aluminum cluster that behaves like a halogen is Al13, and it has a high tendency to accept one electron and form the very stable Al13- ion.

Hey poly, your post got me to do a quick overview of pseudo-halides and by extention superatoms. May my ignorance be excused but it seems Au144(SR)60 is one, and I am a bit confused as to the "SR" part; is that meaning a sulfur and any alkyl inclu. sulfur-hydrogen?
 
Presumably that's describing a gold-sulfur nanoparticle, usually the "SR" is a long chain alkyl thiol, like e.g. C12 thiol.
 
TRI- (and di-) fluoroacetic acids are not toxic in the way that monofluoroacetates, and monofluoroacetic acid esters and IIRC, amides, are. Only fluoroacetic acid and its conjugate bases are able to be metabolized to fluorocitrate and in so doing,
bugger up* the krebs cycle. It isn't fluoroacetate ITSELF that does the damage, not directly. It is first metabolized to fluorocitric acid/fluorocitrate which then acts as a suicide inhibitor of the enzyme aconitase (which, despite the name hasn't a damn thing to do with those most lethally poisonous of plants, the monkshoods, or wolfbane..although there are also several other, unrelated plants that bear the colloquial name 'wolfbane'). Aconitase is vital for inducing a switch in the stereochemistry of citrate from citrate to isocitrate, thus blocking NADH biosynthesis which is essential for driving ATP synthesis and as such, the fluoroacetate is toxic because the body cannot remove the fluorine atom attached to the resulting fluorocitrate, and once bound it blocks enzyme activity. Think of it as the filthy pikey of the mitochondrial toxin world, squirting superglue into the locks, like chavscum vandalizing cars in the same way.



*thats the technical term for such activity;)
 
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