6 bromo 3, 17 dioxoetioallochalane

6-Bromo-3,17-Dioxoetioallocholane

1. Identity: Chemical Names, Structure, and Forms

6-Bromo-3,17-dioxoetioallocholane is a synthetic derivative of the steroidal family, often marketed as a supplement ingredient purported to support hormonal balance and physical performance. The name as it commonly appears in supplement ingredient lists — "6 Bromo 3,17 dioxoetioallochalane" — is a slight variant spelling of the same compound; the standardized chemical name is 6-bromo-3,17-dioxoetioallocholane.

6-Bromo-3,17-dioxoetioallocholane is a synthetic brominated compound structurally related to endogenous steroid hormones. Understanding its name requires understanding the naming conventions for the steroid backbone it is derived from. Androstane is a C19 steroidal hydrocarbon with a gonane core structure. It exists as either of two isomers, known as 5α-androstane and 5β-androstane, which differ in their stereochemistry at the C-5 position. As a basic skeletal structure, androstane serves as the parent compound from which all androgens are derived.

The prefix etioallo- in the name refers to the 5α-androstane skeleton. 5α-Androstane is characterized by the hydrogen atom at position C-5 being in the alpha configuration (below the plane of the ring), resulting in a relatively planar ring system where rings A and B adopt a trans conformation. This isomer is also known by several synonyms, including Aetioallocholan, Etioallocholane, 5α-Androstan, and NSC 49000. This is to be distinguished from the 5β-androstane ("etiocholane") skeleton, which produces a bent, angular A/B ring fusion.

The compound's full systematic name thus describes: a 5α-androstane (etioallocholane) scaffold bearing keto (dioxo) groups at the 3- and 17-positions, and a bromine atom introduced at carbon-6. 6-Bromoandrostenedione (6-BAD) is a derivative of androstenedione, a naturally occurring steroid hormone, and is a prohormone of testosterone.

Common synonyms and related names appearing in the scientific and supplement literature include:

• 6-Bromo-3,17-dioxoetioallocholane (standardized spelling)
• 6-Bromoandrostandione or 6-Bromo androstane-3,17-dione (saturated analog)
• 6-Bromoandrostenedione (the unsaturated Δ4 parent compound most studied in the biochemical literature)
• "6-Bromo" or "6-Bromodione" (common colloquial abbreviations used in the sports supplement industry)

Other names used commercially include: 6 Bromo, 6-Bromo-Androstenedione, and 6-Bromoandrosten[dione]. It is important to note that the supplement-marketed "6-bromo-3,17-dioxoetioallocholane" is the fully saturated (5α-reduced, no Δ4 double bond) form, making it chemically distinct from the more commonly studied 6-bromoandrostenedione (which retains the C4–C5 double bond), although both are classified as brominated C19 steroid derivatives.

Natural Source and Synthesis

6-Bromo-3,17-dioxoetioallocholane is a synthetic brominated compound structurally related to endogenous steroid hormones. While not a traditional herbal extract, its origins and applications in nutritional products draw upon the longstanding medicinal interest in steroidal compounds for their diverse physiological effects. There is no established botanical or natural animal source for this specific brominated compound; it does not occur naturally in significant quantities in the human body or in plants. It is produced through chemical synthesis — specifically through halogenation (bromination) of an androstane precursor molecule at the C-6 position.

The broader chemical class to which it belongs, the brominated androgen derivatives, has been synthesized in pharmaceutical laboratories since at least the 1970s. A series of bromo-4-en-3-one steroid compounds have been reported in the literature, including 6α- and 6β-bromo-androst-4-ene-3,17-dione and its 2,2-dimethyl derivatives, which have significant aromatase inhibitory activity, though the pharmacological mechanisms of the two differ.

Common Forms and Preparations

6-Bromo-3,17-dioxoetioallocholane is often marketed as a supplement ingredient purported to support hormonal balance and physical performance. In the dietary supplement market, it has appeared primarily in the following forms:

• Oral capsules and tablets — the most common delivery format in commercially sold "post-cycle therapy" (PCT) or testosterone-support formulas
• Multi-ingredient blends — in contemporary nutritional products, 6-Bromo-3,17-dioxoetioallocholane is sometimes included in complex herbal formulas aimed at optimizing hormonal health, promoting lean muscle mass, and supporting general well-being in both men and women.

2. Traditional and Historical Use

6-Bromo-3,17-dioxoetioallocholane is a synthetic brominated compound structurally related to endogenous steroid hormones. While not a traditional herbal extract, its origins and applications in nutritional products draw upon the longstanding medicinal interest in steroidal compounds for their diverse physiological effects. Historically, natural and modified steroid analogues have been central to remedies targeting inflammation, stress, and hormonal balance, reflecting their pivotal role in endocrine health.

Because it is a fully synthetic molecule, 6-bromo-3,17-dioxoetioallocholane has no documented traditional or ethnobotanical use in any culture or time period. It has no history in Ayurveda, Traditional Chinese Medicine, Western herbal medicine, or any other traditional medical system. Historically, its use in nutritional products has been driven by anecdotal reports and the broader interest in prohormones and steroidal analogs for sports nutrition.

The compound's appearance in the supplement market belongs to the era of synthetic prohormone and "designer steroid" products that proliferated in the United States from the late 1990s through the 2000s, following the commercial success of androstenedione. In the continued attempts to find supplements that elevate testosterone levels, some companies began manufacturing compounds that have no apparent androgenic activity, but are targeted at increasing the endogenous levels of testosterone by blunting aromatization and subsequent estrogen synthesis.

The biochemical science underlying the compound's marketed use traces back to laboratory research on brominated steroid aromatase inhibitors first published in the mid-1970s, which will be described in the mechanisms section below. No governmental health authority or academic institution has formally endorsed this compound for any medicinal or supplemental purpose.

3. Key Constituents and Established Mechanisms of Action

Structural Chemistry

6-Bromo-3,17-dioxoetioallocholane belongs to the C19 steroid class. Its structure consists of the fully saturated androstane (5α) four-ring steroid scaffold with:

• A 3-keto (carbonyl) functional group on the A ring
• A 17-keto (carbonyl) functional group on the D ring
• A bromine atom substituted at the C-6 position of the B ring

6α-Bromoandrostenedione (6α-BrA) is a competitive inhibitor of human placental aromatase with respect to androstenedione, with an apparent Ki of 3.4 nM, while 6β-BrA is a mechanism-based irreversible inhibitor with an apparent Ki of 0.8 μM and a kinact of 0.025 min⁻¹. This key 1987 publication by Osawa and Coon in Endocrinology (PMID 3622372) established that the stereochemistry of the C-6 bromine substituent — alpha (below the plane) versus beta (above the plane) — fundamentally determines the type and mechanism of aromatase inhibition.

Primary Mechanism: Aromatase Inhibition

6-Bromo is a steroidal aromatase inhibitor, which means it functions by blocking the enzyme aromatase, responsible for converting testosterone into estrogen. By inhibiting this conversion, 6-Bromo is intended to elevate testosterone levels while reducing estrogen levels in the body.

The enzyme aromatase (CYP19A1) is a cytochrome P450 enzyme found in multiple tissues including the gonads, adipose tissue, liver, brain, and adrenal glands. It catalyzes the conversion of C19 androgens (notably androstenedione and testosterone) into C18 estrogens (estrone and estradiol). Brominated androgen derivatives interact with this enzyme at its active site.

Seminal work establishing the pharmacology of brominated androgens as aromatase inhibitors was published in 1976 by Bellino, Gilani, Eng, Osawa, and Duax in the journal Biochemistry. Several brominated androgen derivatives were tested for their ability to inactivate microsomal aromatase from term human placenta. The structures of 6α- and 6β-bromoandrostenedione were unequivocally established by single-crystal X-ray diffraction.

The two stereoisomers act via distinct mechanisms:

• 6α-Bromoandrostenedione (6α-BrA): Competitive inhibition. 6α-BrA is a competitive inhibitor of human placental aromatase with respect to androstenedione, with an apparent Ki of 3.4 nM. Competitive inhibitors reversibly bind to the enzyme's active site, directly competing with the natural substrate (androstenedione) for binding. Because the binding is reversible, inhibition can be overcome by increasing substrate concentration.
• 6β-Bromoandrostenedione (6β-BrA): Mechanism-based (irreversible/suicide) inhibition. 6β-BrA is a mechanism-based irreversible inhibitor with an apparent Ki of 0.8 μM and a kinact of 0.025 min⁻¹. This type of inhibitor is processed by the enzyme during normal catalysis, generating a reactive intermediate that permanently inactivates the enzyme — hence the term "suicide inhibitor."

To gain insight into the mechanism for irreversible inactivation of aromatase by 6β-bromoandrostenedione (1), one of the earliest discovered suicide substrates, in relation to the catalytic function of the enzyme, the 2,2-dimethyl derivative of compound 1, steroid 4, and its 6α-isomer 5, as well as 2-methyl-1,4-diene steroid 8 and its 6α-bromide 10, were synthesized. All of the steroids inhibited aromatase activity in human placental microsomes with apparent Ki values ranging between 10 and 81 nM. The 2,2-dimethyl-6β- and 6α-bromo steroids were extremely powerful inhibitors (Ki: 14 and 10 nM, respectively), but these two did not cause a time-dependent inactivation of aromatase in the presence of NADPH; in contrast, the 2-methyl-1,4-diene steroids caused time-dependent inactivation in a suicide manner.

Because the supplement-marketed compound ("6-bromo-3,17-dioxoetioallocholane") is a mixture or may contain both alpha and beta epimers at C-6, products are often marketed on the premise of providing both modes of aromatase inhibition simultaneously. However, all mechanistic studies cited above were performed on the Δ4 (androstenedione-type) versions of these brominated steroids, not the fully saturated (androstane-type) version. Whether the saturated 5α-analog retains identical potency and mechanism at the aromatase active site has not been definitively confirmed in the independently published peer-reviewed literature.

Secondary Mechanisms: Steroid Hormone Axis Effects

By reducing estrogen biosynthesis through aromatase inhibition, a downstream consequence would be alteration of the hypothalamic-pituitary-gonadal (HPG) axis. Estrogen exerts negative feedback on both the hypothalamus (reducing GnRH release) and the pituitary (reducing LH and FSH release). Suppression of estrogen production by an aromatase inhibitor could therefore theoretically increase LH and FSH output, stimulating testicular testosterone production. It is an aromatase inhibitor and increases levels of testosterone. This affects muscle growth and development, behavior, cognition, and motor function. 6-Bromoandrostenedione also increases levels of other hormones, such as growth hormone, insulin-like growth factor 1 (IGF-1), and erythropoietin (EPO). These claims from a chemical supplier (Santa Cruz Biotechnology) are based on the general pharmacology of aromatase inhibitors as a class; they are not derived from clinical studies specific to this compound.

4. Scientific Evidence by Area of Use

4.1 Aromatase Inhibition and Estrogen Suppression

Evidence Level: Biochemical (in vitro), human placental microsomes only. No controlled clinical trials of the specific compound.

The principal evidence for aromatase-inhibitory activity comes from biochemical studies using human tissue preparations, not from human clinical trials. The 1976 Bellino et al. study (Biochemistry, PMID 974087) demonstrated active-site-directed inactivation of aromatase from human placental microsomes by brominated androgen derivatives. The 1987 Osawa and Coon study (Endocrinology, PMID 3622372) characterized the alpha and beta stereoisomers and their different inhibitory mechanisms. The 2004/2005 Numazawa et al. study (Steroids, PMID 15516742) further explored structure-activity relationships in human placental microsomes.

Research by Budnick and Dao investigated the inhibition of aromatase enzyme in human breast tumors by δ1-testololactone, testololactone, 6α-bromoandrostenedione, and 6β-bromoandrostenedione. Estrone and estradiol synthesis from androstenedione was reduced in tumor incubations by the presence of these agents. 6α- and 6β-bromoandrostenedione (2.0 μM) were also shown to block estrogen synthesis in 2 tumors. Furthermore, Lineweaver-Burk plots revealed that all 4 compounds are competitive inhibitors of androstenedione aromatization.

Scientific validation for the efficacy and safety of 6-bromo-3,17-dioxoetioallocholane remains limited. To date, there have been few, if any, large-scale clinical trials specifically assessing its effects in humans. Some in vitro studies and preliminary animal research suggest that brominated steroid analogs may exhibit aromatase-inhibiting properties, which could theoretically help modulate estrogen and testosterone levels.

4.2 Testosterone Elevation and Hormonal Modulation in Humans

Evidence Level: No direct human clinical trials for 6-bromo-3,17-dioxoetioallocholane specifically. One human trial exists for the structurally related compound 6-OXO (androst-4-ene-3,6,17-trione).

The closest human clinical data available pertains not to 6-bromo-3,17-dioxoetioallocholane itself but to 6-OXO, another purported nutritional aromatase inhibitor with a similar steroidal framework (possessing a ketone rather than a bromine at C-6). This distinction is important but the study provides relevant context for the class of compound. The purpose of this study was to determine the effects of 6-OXO, a purported nutritional aromatase inhibitor, in a dose-dependent manner on body composition, serum hormone levels, and clinical safety markers in resistance-trained males. Sixteen males were supplemented with either 300 mg or 600 mg of 6-OXO in a double-blind manner for eight weeks. Blood and urine samples were obtained at weeks 0, 1, 3, 8, and 11 (after a 3-week washout period).

For all of the serum hormones, there were no significant differences between groups (p > 0.05). Compared to baseline, free testosterone underwent overall increases of 90% for 300 mg 6-OXO and 84% for 600 mg, respectively (p < 0.05). DHT underwent significant overall increases of 192% and 265% with 300 mg and 600 mg, respectively. T/E increased 53% and 67% for 300 mg and 600 mg 6-OXO, respectively.

This study (Rohle et al., 2007, Journal of the International Society of Sports Nutrition, PMC2100070) is notable but has significant limitations: it enrolled only 16 participants, was not placebo-controlled, and involved a different compound (6-OXO, not 6-bromo-3,17-dioxoetioallocholane). Its findings should not be directly extrapolated to the brominated compound.

6-Bromo is used for weight loss, to improve athletic performance, to reduce sexual problems, and for other uses, but there is no good scientific evidence to support its use.

4.3 Body Composition and Athletic Performance

Evidence Level: No clinical evidence. Claims are entirely theoretical or anecdotal.

Its structure is related to certain endogenous hormones, which has led to speculation about its potential to influence muscle growth, fat metabolism, and overall vitality. However, there are no published randomized controlled trials, cohort studies, or case series evaluating the effects of 6-bromo-3,17-dioxoetioallocholane specifically on lean mass, body fat percentage, strength, or exercise performance in human subjects. Claims regarding these outcomes are derived by inference from the general pharmacology of aromatase inhibitors as a drug class — an extrapolation that has not been validated for this specific compound in a supplement context.

4.4 Breast Cancer and Estrogen-Sensitive Tumors

Evidence Level: Biochemical (in vitro) and ex vivo human tumor tissue only. No clinical application.

The original scientific interest in 6-brominated androgen derivatives was as potential therapeutic tools in estrogen-dependent cancers. These results demonstrated that these aromatase inhibitors may be useful for the treatment of breast cancer. However, research in this direction was subsequently superseded by the development of more selective, potent, and better-characterized pharmaceutical aromatase inhibitors (e.g., anastrozole, letrozole, exemestane), which have been approved by regulatory agencies for oncological indications. 6-Bromo-3,17-dioxoetioallocholane has never been developed as a pharmaceutical agent for cancer treatment.

5. Body Systems and Health Areas Associated with This Compound

Based on the available scientific literature, the following body systems are relevant:

• Endocrine / Reproductive System: 6-Bromo is a steroidal aromatase inhibitor that functions by blocking the enzyme aromatase, responsible for converting testosterone into estrogen. By inhibiting this conversion, 6-Bromo is intended to elevate testosterone levels while reducing estrogen levels in the body. The effects — intended or unintended — touch the hypothalamic-pituitary-gonadal axis, adrenal steroid biosynthesis, and sex hormone balance in both males and females.
• Musculoskeletal System: This affects muscle growth and development, behavior, cognition, and motor function. These claims are derived from the known effects of testosterone as a class; no direct musculoskeletal outcome data exist for this compound specifically.
• Hepatic System (Liver): As a steroidal compound processed via hepatic CYP450 enzymes, the liver is central to its metabolism and is the primary organ at risk for adverse effects (see Safety section).
• Etiocholane/Neurosteroid Pathway: The parent skeleton (5α-androstane / etioallocholane) is related to neurosteroid compounds. Etiocholanolone is known to be an inhibitory androstane neurosteroid, acting as a positive allosteric modulator of the GABA-A receptor, and possesses anticonvulsant effects. Whether 6-bromo-3,17-dioxoetioallocholane shares any of these neuroactive properties has not been studied.

6. Dosage Forms and Reported Dosages

There isn't enough reliable information to know what an appropriate dose of 6-Bromo might be. No dose-finding clinical trials or pharmacokinetic studies have been published for 6-bromo-3,17-dioxoetioallocholane in human subjects.

The only doses documented in the peer-reviewed literature for the structurally related 6-OXO (androst-4-ene-3,6,17-trione) compound are: either 300 mg/day or 600 mg/day of 6-OXO assessed over an eight-week oral supplementation period. These dosages are cited here solely for contextual reference; they do not represent established or validated dosages for 6-bromo-3,17-dioxoetioallocholane.

In the dietary supplement market, the compound has been sold in oral capsule form. No pharmacokinetic parameters (absorption, distribution, metabolism, excretion half-life) have been published in peer-reviewed literature for this specific compound. Its oral bioavailability and in vivo metabolic fate in humans are unknown from the published scientific record.

7. Safety Considerations and Interactions

Regulatory Status and Classification

It is banned by the World Anti-Doping Agency (WADA). The World Anti-Doping Agency (WADA) prohibits the use of aromatase inhibitors like 6-Bromo in sports due to their potential to manipulate hormone levels, which can provide an unfair advantage. Athletes subject to anti-doping regulations in any sport governed by WADA-compliant rules should be aware that use of this compound constitutes a prohibited practice.

The FDA has taken action against closely related compounds. An FDA warning letter was issued to Performance Nutrition Formulators LLC dba VMI Sports in May 2018. More broadly, on March 11, 2004, the FDA pronounced that dietary supplement products containing androstenedione were adulterated new dietary ingredients under the Dietary Supplement Health and Education Act of 1994 (DSHEA). The FDA issued a press release, held a news conference, and sent warning letters to 23 companies that had manufactured, marketed or distributed these products, threatening possible enforcement actions for noncompliance.

Adverse Effects

When taken by mouth, 6-Bromo is possibly unsafe for most people. Side effects include liver and kidney damage, behavioral changes, hair loss, and others. It is possibly unsafe for people who are pregnant or breast-feeding, and should be avoided in these populations.

The androgenic and estrogenic disruption associated with steroidal aromatase inhibitors may produce sex-hormone-dependent adverse effects. For androstenedione and related androgen precursors, scientific evidence shows that when such compounds are taken over time and in sufficient quantities, they may increase the risk of serious diseases. Potential long-term consequences in men include testicular atrophy, impotence, and the development of female characteristics such as breast enlargement. Women who use these products may develop male characteristics such as male pattern baldness, deepening of the voice, and increased facial hair. In addition, women may also develop enlargement of the clitoris, as well as abnormal menstrual cycles, abnormal menstrual bleeding, and blood clots.

Hepatotoxicity

As a synthetic steroidal compound, 6-bromo-3,17-dioxoetioallocholane poses hepatic risk. The number of illicit anabolic androgenic steroids inducing liver injury submitted to the DILI Network (DILIN) in the US and to the Spanish DILI Registry has increased in recent years. Cytochrome P450 (CYP450) enzymes metabolize a large number of xenobiotics, which may lead to the formation of hepatotoxic compounds. No specific case reports of hepatotoxicity attributed solely to this named compound have been located in the peer-reviewed literature, but the broader class of androgenic/steroidal dietary supplements carries documented hepatotoxic risk.

Drug and Supplement Interactions

This mechanism [aromatase inhibition] is often utilized in conjunction with anabolic steroid use to mitigate potential side effects such as gynecomastia caused by excessive estrogen production from testosterone. This co-administration pattern carries additive hormonal disruption risk.

Because 6-bromo-3,17-dioxoetioallocholane is structurally related to androstenedione, the interaction profile of the androstenedione class is relevant. Taking androstenedione along with estrogen pills might cause too much estrogen in the body. Some estrogen pills include conjugated equine estrogens (Premarin), ethinyl estradiol, estradiol, and others. Conversely, the aromatase-inhibiting activity of 6-bromo compounds could antagonize the effects of exogenous estrogen therapy.

Herbal supplements that inhibit CYP450 enzymes are problematic, because in addition to affecting the therapeutic efficacy of drugs that require bioactivation for effect, these interactions may inhibit the metabolism of toxic parent compounds to less toxic daughter compounds.

Special Populations

No safety data in pediatric populations, pregnant women, lactating women, or individuals with pre-existing hepatic, renal, or cardiovascular conditions are available in the peer-reviewed literature for this compound. The general principles applicable to androgenic/estrogenic steroidal supplements suggest particular concern in these groups.

8. Overall Evidence Assessment

Scientific validation for the efficacy and safety of 6-Bromo-3,17-dioxoetioallocholane remains limited. To date, there have been few, if any, large-scale clinical trials specifically assessing its effects in humans. Some in vitro studies and preliminary animal research suggest that brominated steroid analogs may exhibit aromatase-inhibiting properties, which could theoretically help modulate estrogen and testosterone levels.

The compound's mechanism of action — aromatase inhibition — is well-established at the biochemical level for related brominated androgen derivatives (6α- and 6β-bromoandrostenedione) in human placental microsome preparations. However, the translation of this biochemical activity to clinically meaningful endpoints in living humans through dietary supplementation has not been rigorously demonstrated for this specific compound. Scientific validation for the efficacy and safety of 6-Bromo-3,17-dioxoetioallocholane remains limited, and to date there have been few, if any, large-scale clinical trials specifically assessing its effects in humans.

The evidentiary hierarchy for this compound is therefore: biochemical/mechanistic (in vitro, human tissue) → weak/absent preclinical animal data → no controlled human clinical trials. All marketed claims for this compound in the context of dietary supplementation go substantially beyond the available peer-reviewed evidence.

References

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