About You

Metandienone Wikipedia

**Metandienone**

*Metandienone*, also known by its trade name *Aromasin*, is a synthetic anabolic–androgenic steroid (AAS) derived from 19‑hydroxyprogesterone. It was first synthesized in the early 1960s and introduced as an oral medication for treating various conditions such as anemia, osteoporosis, cachexia, and androgen deficiency. In sports, it has been used illicitly to enhance muscle mass and performance.

---

### Chemical identity
- **IUPAC name:** (4S,7R,9S,10S,13S,14S,17S)-17‑methyl‑1‑oxo‑2‑4-(propan‑2‑yl)phenoxy‑4,7,9,10,13,14‑hexahydro‑3H‑cyclopenta[a]phenanthren‑6‑yl acetate
- **Molecular formula:** C₂₆H₃₄O₂
- **Molar mass:** 370.52 g mol⁻¹

The molecule is a steroidal core (cyclopenta‑phenanthrene ring system) with an acetoxy‑substituted phenyl ether at the C3 position and a methyl group at C18.

---

## 2. Functional Groups and Their Chemical Behavior

| **Functional Group** | **Location on Steroid Skeleton** | **Key Reactivity / Transformation** |
|----------------------|-----------------------------------|-------------------------------------|
| **Acetoxy group (O‑COCH₃)** | C3 (attached to phenyl ether) | - Acetyl ester hydrolysis → phenolic OH
- Saponification to carboxylic acid
- Transesterification with alcohols |
| **Phenolic ether** | Phenyl ring fused at C2-C3 | - Nucleophilic aromatic substitution (e.g., SNAr with alkoxides)
- Electrophilic aromatic substitution (halogenation, nitration)|
| **Aromatic carbons (C4–C9)** | Ring positions | - Halogenations (Cl, Br) at activated sites
- Friedel-Crafts acylation/alkylation|
| **Side chain at C10** | Methyl group | - Oxidative cleavage to carboxylic acid or aldehyde
- Reduction/oxidation modifications|

---

### 2. Possible Substituents for Introduction

| Substituent | Synthetic Route (brief) | Typical Conditions |
|-------------|------------------------|--------------------|
| **Halogens** (Cl, Br, I) | Electrophilic aromatic substitution using reagents such as NBS (for Br), NCS (for Cl), or I₂/AgNO₃. | 70–90 °C, solvent DMF/Acetone, catalytic amount of Lewis acid (AlCl₃). |
| **Nitro** (–NO₂) | Nitrobenzene derivative via nitration (H₂SO₄/HNO₃) or using metal nitrates in acidic media. | 0–30 °C to avoid over‑nitration, solvent dichloromethane. |
| **Amino** (–NH₂) | Reduction of nitro groups with SnCl₂·2H₂O or catalytic hydrogenation. | 60–80 °C, ethanol/HCl medium; for catalytic H₂ use Pd/C, 1 atm H₂. |
| **Acyl** (e.g., –COCH₃, –C(O)R): Acylation of amines via acyl chlorides or anhydrides. | 0–25 °C, dry pyridine or DMF; avoid water. |
| **Halogen** (Cl, Br, I): Nucleophilic substitution with alkali metal halides or halogenation reagents. | Reflux in acetone or aqueous NaOH; for electrophilic halogenation use NBS, NCS under light/heat. |
| **Oxidation states**: Use appropriate oxidants (e.g., PCC, Jones) or reductants (NaBH4, LiAlH4). | Control stoichiometry; keep temperature low to avoid over‑oxidation. |

---

### 3 Schematic of a \"General\" Organic Synthesis Plan

```
START
|
|--1 Choose target skeleton & identify functional groups
|
|--2 Design retrosynthetic disconnection(s)
| • Select simple precursors (commercial or easily prepared)
| • Aim for 3–4 disconnections to limit steps
|
|--3 For each disconnection, select reaction type
| • Verify availability of reagents & conditions
| • Consider protecting group strategy
|
|--4 Draft forward synthetic route (step‑by‑step)
| • Include purification methods (chromatography, crystallization)
| • Estimate yields; plan for scalability
|
|--5 Evaluate overall feasibility
| • Number of steps 30% per step?
| • Total cost acceptable?
| • Safety and waste considerations
|
|--6 If not feasible, iterate:
| • Re‑evaluate protecting groups
| • Seek alternative reactions
| • Consider starting from a more advanced precursor
|
|--7 Finalize route and prepare detailed experimental plan.
```

---

### 5. Decision‑Making: When to Accept or Reject a Synthetic Route

| **Criterion** | **Acceptable** | **Unacceptable** | **Remedial Action** |
|---------------|----------------|------------------|---------------------|
| **Yield per step (average)** | ≥ 70 % |  15 | Consolidate steps, use tandem reactions. |
| **Availability of starting materials** | Readily available, inexpensive | Rare, expensive | Find alternative precursors, synthetic routes to key intermediates. |
| **Scalability** | Demonstrated at ≥ kg scale | Only milligram scale | Scale-up studies, process chemistry optimization. |
| **Safety** | No highly hazardous reagents or conditions | Use of toxic, explosive, or corrosive agents | Replace with safer alternatives, implement engineering controls. |
| **Environmental impact** | Minimal waste, green solvents | High waste, toxic solvents | Employ green chemistry principles (e.g., solvent-free reactions). |

---

## 4. Comparative Analysis

| Criterion | Approach A (Ring-Closing) | Approach B (Aldol/Cross-Coupling) |
|-----------|----------------------------|-----------------------------------|
| **Synthetic steps** | 1-2 steps (protect, cyclization) | 5+ steps (aldol, reduction, cross-coupling, deprotection) |
| **Reaction conditions** | Mild, room temperature or reflux | Requires harsh bases, high temperatures, transition metals |
| **Reagents** | Standard organometallics (ZnCl₂, TiCl₄), base | Organolithium/Grignard, boronic acids, Pd catalyst |
| **Yield per step** | 70-90% | 40-60% for key steps |
| **Overall yield** | >50% |

Profile Info