17-Iodoandrosta-5,16-dien-3beta-ol
[CAS# 32138-69-5]

Identification

• Classification: Natural product >> Steroidal compound
• Name: 17-Iodoandrosta-5,16-dien-3beta-ol
• Synonyms: (3S,8R,9S,10R,13S,14S)-17-iodo-10,13-dimethyl-2,3,4,7,8,9,11,12,14,15-decahydro-1H-cyclopenta[a]phenanthren-3-ol
• Molecular Formula: C₁₉H₂₇IO
• Molecular Weight: 398.32
• CAS Registry Number: 32138-69-5
• EC Number: 692-056-3
• SMILES: C[C@]12CC[C@@H](CC1=CC[C@@H]3[C@@H]2CC[C@]4([C@H]3CC=C4I)C)O

Properties

• Density: 1.5±0.1 g/cm³ Calc.^*
• Melting point: 175-176 °C (Expl.)
• Boiling point: 447.5±45.0 °C 760 mmHg (Calc.)^*
• Flash point: 224.4±28.7 °C (Calc.)^*
• Index of refraction: 1.618 (Calc.)^*

^* Calculated using Advanced Chemistry Development (ACD/Labs) Software.

Safety Data

• Hazard Symbols: GHS07;GHS08;GHS09 Danger
• Risk Statements: H317-H360-H372-H400-H410
• Safety Statements: P203-P260-P261-P264-P270-P272-P273-P280-P302+P352-P318-P319-P321-P333+P317-P362+P364-P391-P405-P501

Hazard Classification

Hazard	Class	Category Code	Hazard Statement
Acute hazardous to the aquatic environment	Aquatic Acute	1	H400
Reproductive toxicity	Repr.	1B	H360
Skin sensitization	Skin Sens.	1	H317
Chronic hazardous to the aquatic environment	Aquatic Chronic	1	H410
Specific target organ toxicity - repeated exposure	STOT RE	1	H372

Discovery and Applications

17-Iodoandrosta-5,16-dien-3β-ol is a synthetic steroid derivative characterized by an iodinated modification at the 17-position of the androsta-5,16-dien backbone, with a 3β-hydroxyl group. The incorporation of iodine into the steroid nucleus confers distinctive chemical and biological properties, making the compound relevant for studies in steroid chemistry, radiolabeling, and receptor binding assays. Such iodinated steroids are often utilized as intermediates in the synthesis of radiolabeled analogs for imaging or mechanistic investigations of steroid hormone pathways.

The discovery of 17-iodoandrosta-5,16-dien-3β-ol stems from research into functionalized steroid derivatives, particularly for use in receptor binding studies and chemical biology. The introduction of the iodine atom at C17 is typically achieved via halogenation reactions of corresponding 17-keto or 17-hydroxy steroid precursors under controlled conditions, ensuring regioselectivity and retention of the stereochemistry at C3. The double bonds at positions 5 and 16 contribute to the conjugated diene system, which can influence the molecule’s reactivity and interaction with steroid receptors.

In synthetic chemistry, 17-iodoandrosta-5,16-dien-3β-ol serves as a versatile intermediate. The C17 iodide can participate in nucleophilic substitution, cross-coupling reactions, or radiolabeling with iodine isotopes such as ¹²³I or ¹²⁵I. These transformations allow the preparation of labeled steroids for positron emission tomography (PET) or single-photon emission computed tomography (SPECT) imaging, facilitating the study of steroid metabolism and receptor distribution in vivo. The 3β-hydroxyl group can also undergo selective derivatization to produce esters, ethers, or conjugates, expanding the range of chemical modifications possible.

The compound’s structural features make it a useful probe in endocrinology and pharmacology. Iodinated steroids like 17-iodoandrosta-5,16-dien-3β-ol can bind to androgen or other nuclear receptors, enabling investigations into receptor affinity, selectivity, and signaling. Additionally, its functionalization at C17 allows the incorporation of radiotracers without significantly altering receptor binding characteristics, making it suitable for mechanistic and imaging studies in both cell-based and in vivo systems.

The preparation of 17-iodoandrosta-5,16-dien-3β-ol generally involves careful control of reaction conditions to prevent side reactions such as overhalogenation or double-bond migration. Protection of the 3β-hydroxyl group is often employed during iodination to ensure selectivity, followed by deprotection to yield the free alcohol. The resulting compound is typically isolated as a crystalline solid or purified by chromatography, depending on the scale and desired purity.

Applications of 17-iodoandrosta-5,16-dien-3β-ol extend to research in steroid biosynthesis and metabolism, where iodinated derivatives are used to track enzymatic transformations or receptor interactions. Its ability to serve as a precursor for radiolabeled analogs enhances its utility in medical imaging and diagnostic studies, providing insights into endocrine function, hormone-dependent cancers, and steroid pharmacokinetics.

Overall, 17-iodoandrosta-5,16-dien-3β-ol is a functionally versatile steroid derivative with applications in synthetic chemistry, receptor binding studies, and radiolabeling. Its structural characteristics, including the C17 iodide, conjugated dienes, and 3β-hydroxyl group, make it a valuable tool for both chemical and biological investigations of steroid-related processes.