4-chlorodehydromethyltestosterone (AKA Turinabol, Oral Turinabol, Tbol)
Chemical Name: 4-chloro-17a-methyl-17b-hydroxyandrosta-1,4-dien-3-one
Molecular Weight: 334.89 g/mol
Original Manufacturer: Jenapharm
Half Life: 16 hours
Detection Time: 11 – 12 months
Anabolic Rating: 54
Androgenic Rating: 6
Overview and History of Turinabol
Turinabol (Chlorodehydromethyltestosterone, also known as ‘Tbol’ and Oral Turinabol) is actually a modified form of Dianabol (Methandrostenolone), whereby it is actually a combination of the chemical structures of Dianabol and Clostebol (4-chlorotestosterone). Hence this is why the actual chemical name is 4-chlorodehydromethyltestosterone. The modifications to its chemical structure allow it to be non-aromatizable and to also possess a very low androgenic rating, which is likely why Turinabol has been nicknamed as a ‘mild Dianabol’.
Information in regards to Turinabol was first published in 1962 and Chlorodehydromethyltestosterone was then manufactured and released by Jenapharm in East Germany as Turinabol and Oral Turinabol. Much like other compounds such as Anavar (Oxandrolone), Turinabol was revered by medical personnel and physicians for its ability to provide a fairly distinct separation of its anabolic and androgenic effects, favoring anabolic effects of course. This is one of the reasons why its often compared to compounds such as Anavar or Promobolan. As a result, much like Anavar or Primobolan, Oral-Turinabol saw extensive medical use in not just adult males but in women and children also. At the time, Turinabol was offered in two different concentrations per tablet: 1mg tablets, and 5mg tablets. The 1mg tablets would typically be utilized for individuals traditionally more sensitive to anabolic steroid therapies, such as women and children. Under its medical use at the time, it was prescribed for many different ailments, but was used frequently for the promotion of fat free mass in wasting disorders as well as the promotion of bone strength and mass.
Later in the 1990s, it was discovered that Turinabol was one of the key anabolic steroids utilized by East Germany in their infamous state-sponsored doping program known as the State Plan Research Theme 14.25. This plan was developed by the East German government in the late 1960s and implemented between 1974 – 1989 for the explicit purpose of administering anabolic steroids to all of their athletes (whether unbeknownst to them or not) in order to dominate at the Olympic games and other international sporting events. The core goal of this program was to simply cheat the anabolic steroid testing system in the Olympics by administering what would be at the time undetectable (due to its existence not being relatively well known) anabolic steroids to unwitting athletes, both male and female, who were simply told by their trainers and coaches that they were being given tiny blue vitamins. It later became known that the majority of these “vitamins” was, in fact, Oral-Turinabol. It was discovered that approximately 10,000 athletes over the course of a little over two decades were administered anabolic steroids (with most being Turinabol), whether they had known it or not.
Although Tbol had expressed an incredible record of valid application and safety, in 1994 Jenapharm halted production. This was a time in the early 1990s when the majority of anabolic steroids had been discontinued and pulled from markets all across the world due to the increasing anti-steroid stigma at the time. The increasing amounts of negative attention drawn to the use of anabolic steroids in sports in the early 1990s did not help Turinabol’s case, and its fate at the time was similar to many other anabolic steroids at the time as well. Jenapharm was eventually bought by Schering AG in 1996, but did not resume the manufacture of Turinabol. The halted production in the early 1990s coincided with the details concerning East Germany’s state sponsored doping program coming to light, and its abrupt production halt alongside the news in regards to the doping program is likely what contributed to the popular attitude among athletes and bodybuilders that Turinabol was a very mysterious, special, and prized anabolic steroid to obtain.
Today there are no known pharmaceutical productions of this compound, and its production is limited to underground lab (UGL) manufacturers.
Chemical Characteristics of Turinabol
As previously mentioned, Tbol is in reality a modified form of Dianabol (Methandrostenolone), whereby it is actually a combination of the chemical structures of Dianabol and Clostebol (4-chlorotestosterone). It possesses the same general chemical structure of Dianabol along with the 4-chloro substitution that Clostebol possesses. The result is that Tbol becomes a much milder hormone than its parent hormone Dianabol. The alterations to its chemical structure remove the ability for it to be able to be aromatized into Estrogen, as well as exhibiting a far weaker androgenic strength. Turinabol therefore possesses an anabolic rating of 54, and a very low androgenic rating of 6, making its separation between anabolic and androgenic effects very distinct and favorable. Although the anabolic strength is considerably less than Dianabol’s rating of 90 – 210, the distinct distance between Turinabol’s anabolic and androgenic effects tend to be far more favorable to the individual.
Turinabol’s chemical modifications also grant it a 16 hour half-life as well as the ability to bind to SHBG (Sex Hormone Binding Globulin).
Turinabol is C17-alpha alkylated so as to allow oral bioavailability, and as a result, will exhibit a measure of liver toxicity. It also possesses a double bond between carbon 1 and carbon 2 (also known as the 1-ene carbon), and it is this double-bond that is responsible for the reduction of androgenic strength. Lastly, as previously mentioned, a chloro group has been added at the 4th carbon, responsible for rendering it unable to aromatize as well as reducing the androgenic strength even further.
Properties of Turinabol
Because of its distinct separation of its androgenic to anabolic effects, it is a weaker anabolic steroid than its parent hormone Dianabol. However, the assurance with Tbol is that with any apparent muscle building capability, it will present much less in the way of androgenic effects and absolutely no estrogenic effects (due to its inability to aromatize into Estrogen). Because of its fairly weaker strength than Dianabol, the doses required to elicit effects from Tbol are considered to be quite high (this will be explained shortly in the Turinabol doses section of this profile).
In general, athletes and bodybuilders can expect steady and quality lean mass gains with no risk of any bloating, gyno, or any other estrogenic effects. Mass and strength gains are not known to be dramatic due to its lack of anabolic strength, but steady and quality lean gains that grow consistently over time can be expected. It is also used as an ideal cutting agent during periods of fat loss or pre-contest preparation due to its inability to convert into Estrogen. Turinabol’s capabilities really shine as an adjunct to other anabolic steroids when it is run (stacked) with other anabolic steroids due to its ability to bind to SHBG. Binding to SHBG allows more of the other anabolic steroids it is stacked with to be available to do their job, being uninhibited by SHBG, which is another advantage that it exhibits.
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 Department of Urology, Universitaetsklinikum. Carl Gustav Carus. Technical University of Dresden,Dresden, Germany.