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LabRat
11-12-2003, 09:51 PM
Steriod Esters
STEROID ESTERS
by Roy Harper

It seems many people know very little about steroid esters. Many people believe it is the ester that determines the anabolic potential for any steroid. But in reality, there is absolutely no difference, in anabolic strength, from one ester to the other. Testosterone suspension is the same as Testosterone cypionate once the cypionate ester has been cleaved off by esterases in your body. Testosterone is testosterone no matter how you look at it. Now before you roll me up in a carpet and throw me over a bridge, I will admit that there is a large difference in how esters affect the release of the steroid. The key is time release (read half-life). Esters essentially delay the release of a steroid. Regardless of whether you injected 500mg of Testosterone suspension or 500mg of Testosterone cypionate, you will end up with approximately 500mg Testosterone in your system (ok, there is going to be slightly less testosterone with the cypionate because of the weight of the ester, but I’ll explain that later). The difference between the two is that all of the 500 mg of testosterone suspension would be available and metabolized within 24 hours, whereas after a week half of the testosterone in the cypionate would be released. Is that it? That's all what esters do? Of course not! In fact the real purpose for esters is to change the properties of the parent drug. As shown above the half-life, can be altered through the use of an ester.

Let's go through some of the details about esters. Steroid molecules are carbon based, as with any earthly organic molecule. The base of the molecule is formed with a chain of carbon molecules. At the 17th position, i.e. the 17th carbon atom, there is a hydroxyl group (OH) that is bonded there. This is where the fun comes in, when this base steroid is hydrolyzed (removing the OH group) an ester can be added here. With the addition of the ester the solubility in oil can be changed, the half-life can be changed, etc. To add to this, the more carbon atoms the ester has the more solubility in oil increases and the half life increases. Therefore, esters such as acetic acid (two carbons) and propionic acid (three carbons) aren't as soluble and have a quick half live. On the other hand, esters such as decanoic acid (ten carbons) and undecanoic acid (eleven carbons) are very soluble in oil and have longer half lives.

Well let's put esters on everything! How about those 17Alpha Alkylated steroids? You know the ones that are orally active. Well, as with esters, there is an extra chemical that is added at the 17th position. What's added is a 17-methyl group. This is what makes winstrol and dianabol great steroids. Without them the liver would metabolize these steroids instantaneously. A 17AA steroid ester without the 17-methyl group would be inactive. A 17AA steroid ester attached with the 17-methyl group would prevent the base steroid from being removed from the ester. Although I've heard rumors that 17AA esters have been made, I highly doubt it's even possible.

And now for the juicy part, how to make your esters at home. Note this is a theoretical discussion and not actual instructions. It would be very dangerous not only in the process of esterfication but also injecting the resulting product. With all that said, first we need to begin with a base steroid. The easiest would be using USP grade powder. Then you would add in one part of anhydrid of the ester you want, to two parts of pyridine. For example you would add in 500mg of cypionic anhydride to 250mg pyridine. Then the base steroid would react within this mixture at ten parts mixture to one part base steroid. Once the reaction has occurred you would then purify the mixture with twenty parts water and one part ether. Decant the water while adding it to another ten parts water. Once complete, simply recrystalize the steroid, and there you have it. A steroid ester made at home. But remember if you aren't a chemist you should not even think of doing this.

Well let’s look at the opposite side of the spectrum. Suppose you want to remove the ester from a steroid ester. Start by dissolving the steroid ester in water. If the ester is already in an oil solution then you better know what the oil is and look it up in the Merck index to figure out how to remove either the oil or steroid ester. Once dissolved in water the ester can be removed. As above you need to use the Merck index to figure it out for each ester. If you got this far then you have your very own base steroid.

You may be thinking to yourself "If this is so complicated, how come our bodies can do it so easily?" Well the answer my friend is invariably, enzymes. Ahh the power of enzymes. Is there anything they can't do? Well looking closer at how our bodies do it, we see that the enzyme esterase is responsible for this process. It follows the same procedure above, technically speaking, and requires water to break the steroid from the ester. But the more oil and the more soluble in oil the steroid ester becomes, the harder it is for esterase to perform its duty. The use of other enzymes to remove the steroid ester from the oil which will lengthen the amount time until the ester is removed. Hence the change in half-life for longer chained esters.

Remember the ester does not determine the anabolic properties of a steroid. With this in mind, please recall that you should consider the timing of injections and the purpose for the steroid. For example Testosterone propionate could be used for a very short cycle. While Nandrolone decanoate would be used in a longer cycle. If you want to determine the half-life of a steroid ester use the following guide:
Ester Number of Carbon Atoms
Formate 1
Acetate 2
Propionate 3
Butyrate 4
Valerate 5
Hexanoate 6
Heptanoate 7
Enanthate 7
Octanoate 8
Cypionate 8
Nonanoate 9
Decanoate 10
Undecanoate 11



If the ester you're looking is not here, simply look on the Internet to find how many carbon atoms there are in the ester. Approximately each carbon atoms is equal to a half-life of 1.5 days. Therefore a decanoate steroid ester would have a half-life of 15 days (11 carbon atoms * 1.5 days constant). In case you're wondering what the half-life is, it's the amount of time before half of the original substance is used. For instance 15 days after an injection of 200mg of deca, 100mg would be left.

Now, you have to remember that the ester is going to add more weight to the molecule. The larger the ester the less base steroid there is going to be in a 100mg steroid ester. You can use the following chart to figure this out:


Chemical Formula

Molecular Weight

Mg of Testosterone
Testosterone (no ester)
C19 H28 O2 288.4 100mg
Acetate
C2 H2 O 42.1 87.26mg
Propionate
C3 H4 O 56.1mg 83.72mg
Enanthate*
C7 H12 O 112.2mg 71.99mg
Cypionate
C8 H4 O 124.2mg 69.90mg
Decanoate
C10 H18 O 154.3mg 65.15mg

Undecanoate info not availible
*Data Extrapolated from another formula (may not be exact)

Hopefully all of this has educated you in the wonderful world of esters. Never again will you wonder about the difference between acetate and undecanoate.

gandhisays
01-28-2013, 09:55 AM
Copied to Articles! 10 years old but worth a read!