Bromantane is a laboratory reagent whose structure is unusually convenient to verify: a saturated cage hydrocarbon, an aromatic ring and a bromine atom each leave a distinct trace in a different instrument. The notes below describe how such a batch is identified and how its purity is judged.
Chemical identity of the sample
The framework consists of an adamantane cage bonded through a secondary nitrogen atom to a phenyl ring bearing bromine in the para position. The rigid saturated cage accounts for pronounced lipophilicity and negligible solubility in water, which is why stock solutions are prepared in organic solvents. The aromatic fragment supplies ultraviolet absorbance, and the bromine atom supplies the decisive isotope signature in mass spectrometry. See also our laboratory reagent listing: Coluracetam, czystość substancji ≥ 99%, 1000mg.
- CAS number
- 87913-26-6
- Molecular formula
- C16H20BrN
- Molar mass
- 306.25 g/mol
- Systematic name
- N-(4-bromophenyl)tricyclo[3.3.1.1³,⁷]decan-2-amine
- Structural fragments
- adamantane cage, secondary aromatic amine, bromophenyl ring
- Names in the literature
- bromantan, ADK-709, and the trade designation Ladasten — one and the same molecule
- Solubility
- good in organic solvents, negligible in water
Chromatography — HPLC and GC
Reversed-phase liquid chromatography retains this material strongly, so the mobile phase needs a high proportion of organic modifier, occasionally a gradient reaching nearly neat acetonitrile. Ultraviolet detection exploits the bromophenyl chromophore, and a diode-array detector adds a second criterion: the spectrum taken on the rising edge of a peak must match the spectrum on the falling edge, otherwise two components are hiding under one maximum.
A retention time proves nothing on its own. It belongs to one combination of column, mobile phase and temperature, and becomes evidence only in relative form, referenced to a standard injected in the same sequence, and only when a spiked injection leaves the peak single and symmetrical.
Unlike thermally fragile compounds, this molecule survives the gas chromatographic inlet, which makes gas chromatography coupled to mass spectrometry a natural confirmation tool: an electron ionisation spectrum can be matched against a spectral library. Peak shape may suffer from interaction of the secondary amine with active sites in the liner; deactivating the sample path or converting the amine into an acyl or silyl derivative restores symmetry. A separate headspace run covers residual solvents.
Spectroscopic methods
Mass spectrometry
The bromine isotope pattern is the strongest single argument available here. The element has two stable isotopes of comparable natural abundance, so every bromine-containing ion appears as a pair of signals two mass units apart and of nearly equal height. That picture separates brominated ions from the rest of the spectrum at a glance. A second recognisable feature is the exceptionally stable cation derived from the hydrocarbon cage, which usually dominates the fragmentation region. High-resolution measurement confirms elemental composition and rules out coincidental agreement of nominal masses.
NMR
In the proton spectrum, para substitution of the ring produces the familiar picture of four aromatic protons resolved into two signals of similar shape. The proton on nitrogen is broad and disappears after shaking the sample with deuterium oxide. The cage generates a crowded envelope in the aliphatic region; substitution at the second position lowers its symmetry, increasing the number of resolvable lines in the carbon spectrum. The carbon bonded to bromine gives a quaternary signal at a characteristic position.
Infrared (IR)
The spectrum is dominated by intense aliphatic carbon–hydrogen stretching bands from the saturated cage. Added to these are a single nitrogen–hydrogen stretch typical of a secondary amine, aromatic ring bands, and a carbon–bromine band in the low wavenumber region. Agreement across the whole fingerprint region with a reference spectrum, rather than any single band, is what settles identity.
Impurities and degradation products
- Unreacted starting materials: the brominated aromatic amine and the cage ketone.
- Ring isomers differing in the position of bromine, formed when bromination is insufficiently selective.
- The bromine-free analogue, hard to see by ultraviolet detection yet obvious in mass spectra through the missing isotope pair.
- A dibrominated by-product of higher mass, recognisable by an isotope cluster of three lines.
- Oxidation products of the secondary amine, usually announced by yellowing of the solid.
- Inorganic salts carried over from work-up.
- Residual solvents and water bound to the material.
Sample collection and storage
| Item | Practice |
|---|---|
| Container | amber glass with a PTFE-lined closure; soft plastics are unsuitable for a lipophilic solid |
| Light | strict protection — an aryl–bromine bond can be sensitive to radiation |
| Atmosphere | an inert gas layer over archive material limits oxidation of the amine |
| Moisture | desiccant in the outer packaging; open only at room temperature |
| Sampling | a dedicated spatula per batch; mass recorded before and after |
| Working solutions | prepared in acetonitrile or methanol before a sequence, kept from light |
| Labelling | systematic name, CAS number, batch number, date of opening |
Batch documentation
A certificate of analysis is useful only when tied to one physical container. It should state the batch number, manufacturing and retest dates, the assay method with its result, and the reporting threshold above which individual impurities are listed. For a brominated compound it is worth attaching the raw mass spectrum, because the isotope pair is a criterion any reviewer can verify without repeating the assay.
Trade synonyms printed on a supplier label deserve a separate entry: the systematic name and CAS number are the primary identifiers in the reagent register, a trade designation only a cross-reference. Every discrepancy between supplier declaration and in-house measurement is logged as a deviation before release. See also our catalogue item: Phenylpiracetam / Phenylpiracetam, Purity ≥ 99%, 100.
Handling qualification. Any administration to humans is excluded. The material is not a veterinary product. It is a high-purity laboratory product for research using HPLC and GC-MS. Outside the category of medicinal and food products.
Reagents of a similar class
- Phenylpiracetam / Phenylpiracetam, Purity ≥ 99%, 1000mg
- Coluracetam, czystość substancji ≥ 99%, 1000mg
- Alfa GPC, czystość ≥ 99% waga 1000mg netto.
- Mebicar / Mebikar / Temgicoluril – Czystość ≥ 99%
References
Records indexed in PubMed for this substance; each entry is identified by its PMID.
- Iëzhitsa IN, Eksperimental'naia i klinicheskaia farmakologiia, 2000 — PMID 11109517
- Bugaeva LI, Eksperimental'naia i klinicheskaia farmakologiia, 2000 — PMID 10763112
- Seredenin SB, Biulleten' eksperimental'noi biologii i meditsiny, 1999 — PMID 10640239
- Morozov IS, Eksperimental'naia i klinicheskaia farmakologiia, 1998 — PMID 9929819
