Introduction
C13H11NO3 denotes a small organic molecule comprising thirteen carbon atoms, eleven hydrogen atoms, one nitrogen atom, and three oxygen atoms. The molecular formula is characteristic of a class of heteroaromatic compounds that often contain an indole or benzoxazole core with additional functional groups such as carbonyl or hydroxyl groups. These structural motifs endow the molecule with distinct physicochemical properties and biological activities that have attracted attention in medicinal chemistry, materials science, and natural product research. The present article compiles current knowledge on the structural aspects, synthesis routes, natural occurrence, applications, and safety considerations associated with this molecular entity.
Chemical Properties
Physical Characteristics
Compounds with the formula C13H11NO3 typically manifest as solid crystals or colorless to pale yellow powders at room temperature. The melting point of representative derivatives ranges from 110 °C to 180 °C, depending on substituent pattern and crystal packing. Solubility studies indicate moderate solubility in polar organic solvents such as methanol, ethanol, and acetonitrile, whereas solubility in nonpolar solvents like hexane is limited. The presence of the nitrogen atom within an aromatic ring increases the basicity of the heterocycle, whereas the oxygen-containing carbonyl or hydroxyl functionalities contribute to hydrogen-bonding capacity, influencing both solubility and melting behavior.
Spectroscopic Data
In nuclear magnetic resonance (NMR) spectroscopy, the ^1H NMR spectrum of a typical C13H11NO3 compound exhibits an aromatic region between 6.5 and 8.5 ppm, reflecting protons on the heteroaromatic ring system. A singlet or multiplet between 7.0 and 7.5 ppm is usually observed for protons on a phenyl substituent, while a downfield signal around 12–13 ppm indicates a phenolic OH proton engaged in strong intramolecular hydrogen bonding. The ^13C NMR spectrum shows signals between 110 and 160 ppm for aromatic carbons and a distinct carbonyl resonance near 170–180 ppm. Infrared (IR) spectroscopy typically displays characteristic absorptions at 1680–1750 cm^−1 for the carbonyl stretch and at 3400–3600 cm^−1 for the hydroxyl O–H stretch. Mass spectrometry yields a molecular ion at m/z 229, consistent with the calculated monoisotopic mass of 229.1 Da.
Synthesis and Derivatives
Laboratory Synthesis
Several synthetic routes are documented for constructing a C13H11NO3 skeleton. A common strategy employs a Friedel–Crafts acylation of an indole derivative with an activated acyl chloride, followed by cyclization to close the heterocyclic ring. For instance, reacting 3-bromoindole with 2-bromobenzoyl chloride under Lewis acid catalysis (AlCl_3) can produce a bromoindolinone intermediate, which, after intramolecular nucleophilic substitution, yields the desired heterocycle. Alternatively, a condensation between 2-hydroxynaphthaldehyde and an aniline derivative in the presence of a dehydrating agent such as polyphosphoric acid affords a benzoxazole core bearing a carbonyl group and a hydroxyl substituent. Subsequent protection–deprotection steps allow for the introduction of additional functional groups, expanding the chemical space of the molecule.
Another effective approach is a one-pot, multicomponent reaction (MCR) that couples an aldehyde, an amine, and a β-ketoester. The Hantzsch reaction, for example, can be adapted to generate an indole-3-carboxylate framework, which after decarboxylation and oxidation yields the target C13H11NO3 compound. Reaction yields typically range from 45 % to 75 %, with the main side products being over-acylated or polymerized species that can be removed by recrystallization.
Biological Synthesis
In natural settings, the C13H11NO3 core may arise through enzymatic pathways that assemble indole or benzoxazole rings from tryptophan or phenylalanine precursors. For example, certain marine fungi produce indole alkaloids containing a 1,3-benzoxazinone scaffold, which is derived from oxidative coupling between an indole ring and a phenolic unit. The enzymatic oxidation steps involve oxidoreductases that introduce carbonyl functionalities, while dehydrogenases create the heteroaromatic system. Although the precise enzymatic sequence for this particular formula is not fully resolved, comparative genomics suggests the involvement of nonribosomal peptide synthetases and tailoring enzymes that catalyze ring closure and functional group installation.
Natural Occurrence
The structural motif represented by C13H11NO3 is found in a variety of secondary metabolites isolated from plants, fungi, and marine organisms. Many of these natural products are classified as indole alkaloids or benzoxazoles and exhibit notable bioactivity. For example, a marine-derived fungus belonging to the genus Aspergillus has yielded a series of benzoxazinone compounds with the same molecular formula, displaying moderate cytotoxicity against cancer cell lines. Similarly, a shrub of the family Solanaceae has been reported to contain an indole-3-carboxylate derivative that contributes to its bitter taste and antimicrobial properties. In these contexts, the molecule is typically isolated through solvent extraction followed by chromatographic purification, with structure elucidation confirmed by spectroscopic techniques.
Beyond isolated compounds, the C13H11NO3 framework appears in complex mixtures such as essential oils, where it may act as a minor component with flavor or fragrance properties. The prevalence of this scaffold in diverse ecological niches underscores its evolutionary utility, possibly serving as a deterrent against herbivory or as a signaling molecule in symbiotic interactions.
Applications
Pharmacology
Medicinal chemistry investigations have identified several analogues of the C13H11NO3 core with promising pharmacological profiles. One notable class involves 3-substituted indolin-2-one derivatives that function as selective inhibitors of cyclin-dependent kinase 2 (CDK2), showing potential for cancer therapy. The hydroxyl group contributes to hydrogen-bonding with the ATP-binding pocket of CDK2, while the aromatic system affords hydrophobic interactions that enhance binding affinity. Another subclass targets the enzyme acetylcholinesterase; the presence of the nitrogen atom in a heteroaromatic ring allows for π–π stacking with the enzyme's active-site residues, thereby inhibiting neurotransmitter breakdown.
In addition, the benzoxazole analogues have been examined for anti-inflammatory activity. The carbonyl group and phenolic OH participate in the inhibition of prostaglandin E2 synthesis, as demonstrated in in vitro assays with isolated macrophage cultures. The anti-inflammatory efficacy is often correlated with the electronic nature of substituents on the benzoxazole ring, suggesting a structure–activity relationship that guides further optimization.
Materials Science
Organic electronic materials have leveraged the C13H11NO3 scaffold to develop new organic light-emitting diodes (OLEDs) and field-effect transistors (OFETs). The extended conjugated system offers a favorable balance between electron-rich and electron-deficient character, enabling efficient charge transport. For instance, a 2,7-diarylindolo[3,2-b]pyridine derivative based on this formula exhibits a high photoluminescence quantum yield and emits in the blue region, making it suitable for display technologies. In OFETs, the inclusion of a carbonyl group enhances electron affinity, allowing for ambipolar transport when combined with appropriate donor–acceptor substitution patterns.
Furthermore, the molecule's capacity to form hydrogen bonds through its phenolic OH group and carbonyl oxygen makes it a suitable candidate for self-assembly into supramolecular architectures. Such assemblies can be used to fabricate thin films with controlled porosity, useful in gas separation membranes or as catalytic supports in heterogeneous catalysis.
Other Uses
Beyond pharmaceuticals and electronics, the C13H11NO3 core finds application in agrochemicals. Certain indole-derived fungicides contain this scaffold, exhibiting activity against fungal pathogens by disrupting the cell membrane integrity. The hydroxyl group contributes to environmental degradation pathways, allowing for biodegradation under aerobic conditions. In the fragrance industry, the benzoxazole derivative is employed as a fixative that prolongs the longevity of scent molecules in perfumery formulations, owing to its moderate volatility and ability to form stable complexes with other aromatic compounds.
In analytical chemistry, labeled derivatives of this formula are used as internal standards in chromatographic assays for environmental monitoring of indole-containing pollutants. Their distinct mass spectra and retention times facilitate accurate quantification of trace-level contaminants in water and soil samples.
Safety and Handling
Compounds with the C13H11NO3 formula are generally considered to possess low acute toxicity; however, safety data sheets recommend standard laboratory precautions. Exposure routes include inhalation of dust or vapor, dermal contact, and ingestion. Protective equipment such as gloves, goggles, and lab coats should be worn when handling solid powders. In the event of inhalation, the material should be dispersed in a well-ventilated area, and any inhaled dust should be cleared by gentle coughing. Skin contact should be minimized, and contaminated clothing should be washed promptly. Ingestion is unlikely under normal laboratory conditions, but accidental ingestion should be treated with immediate medical attention.
Flammability tests indicate that the compound has a flash point above 200 °C, indicating limited flammability under typical laboratory conditions. It is not considered a strong oxidizer or reducing agent. The compound should be stored in a cool, dry place, protected from direct sunlight. Proper waste disposal methods include collecting spent material in designated containers for hazardous chemicals and following institutional protocols for disposal or recycling. Environmental impact is generally low, but large-scale production may require monitoring of effluent streams for residual organic content.
No comments yet. Be the first to comment!