---
title: "Alanine Structure (C3H7NO2): 3D Model, Formula & Molar Mass | MolDraw"
url: https://www.moldraw.com/molecules/alanine.html
description: "Structure of Alanine (C3H7NO2, 89.09 g/mol): rotatable 3D model, 2D skeletal formula, IUPAC name, SMILES, shape, polarity, uses and FAQ."
lang: en
publisher: Scidart Academy
generated: 2026-10-26
---
[MolDraw](https://www.moldraw.com/) › [3D molecule models](https://www.moldraw.com/molecules/) › Alanine structure

# Alanine structure and 3D model (C3H7NO2)

L-alanine is the simplest chiral amino acid. Its side chain is a single methyl group on the α-carbon.

**Quick answer:** Alanine is **C3H7NO2**, molar mass **89.09 g/mol**. Small tetrahedral molecule that exists as a zwitterion; very polar and freely soluble in water.

Atom labels Hydrogens Spin

Drag to rotate · pinch or scroll to zoom. 3D coordinates: computed with RDKit (ETKDG conformer, force-field optimised).

## Alanine at a glance

| Formula | C3H7NO2 |
| --- | --- |
| Molar mass | 89.09 g/mol |
| IUPAC name | (2S)-2-aminopropanoic acid |
| Atoms / bonds | 13 / 12 |
| H-bond donors / acceptors | 2 / 2 |
| logP (estimated) | -0.6 |
| SMILES | `C[C@@H](C(=O)O)N` |
| InChIKey | `QNAYBMKLOCPYGJ-REOHCLBHSA-N` |
| PubChem | [5950](https://pubchem.ncbi.nlm.nih.gov/compound/5950) |

![2D structural formula of Alanine (C3H7NO2)](https://www.moldraw.com/molecules/img/alanine.svg)

2D structure (skeletal formula) · [Draw it in MolDraw](https://www.moldraw.com/)

## What the 3D model of Alanine shows

The model contains **13 atoms** (6 heavy atoms and 7 hydrogens) joined by **12 bonds**; in ball-and-stick mode every stick is one bond, and double or aromatic bonds are drawn as multiple sticks. Switch to *space-filling* to see the molecule as its electron cloud, scaled to van der Waals radii: this is the shape other molecules actually "feel". It can donate 2 and accept 2 hydrogen bonds, and its estimated logP of -0.6 means it is very water-loving (hydrophilic). Its topological polar surface area is 63 Ų.

## Shape and bond angles

| Atom(s) | Geometry / hybridisation | Angles & lengths |
| --- | --- | --- |
| α-carbon | Tetrahedral, sp³; stereocentre (S) | ≈ 109.5° |
| carboxyl carbon | Trigonal planar, sp² | ≈ 120° |
| amino N | Tetrahedral as NH₃⁺ in the zwitterion | ≈ 109.5° |

### Is Alanine polar?

Yes. In water and in the solid it exists as a zwitterion, H₃N⁺–CH(CH₃)–COO⁻, which is highly polar.

## Elemental composition of C3H7NO2

| Element | Atoms | Mass (g/mol) | Mass % |
| --- | --- | --- | --- |
| Carbon (C) | 3 | 36.033 | 40.44% |
| Hydrogen (H) | 7 | 7.056 | 7.92% |
| Nitrogen (N) | 1 | 14.007 | 15.72% |
| Oxygen (O) | 2 | 31.998 | 35.91% |

Calculated from IUPAC standard atomic weights. Check any formula with the [molar mass calculator](https://www.moldraw.com/tools/free-chem-tools/molar-mass-calculator.html).

## Uses of alanine

- One of the 20 amino acids that make up proteins
- Carries nitrogen from muscle to the liver (glucose–alanine cycle)
- Used in sports supplements and food flavouring

## Interesting facts

- Alanine was first synthesised by Adolph Strecker in 1850.
- Its name may come from acetaldehyde, the starting material in that synthesis.
- Alanine has been found in meteorites, in both L and D forms.

**Drawing structures for your notes?** MolDraw is a free online chemical structure editor for molecules, reactions and lab diagrams.

[Open MolDraw editor](https://www.moldraw.com/)

## Frequently asked questions

### What is the structure of Alanine?

L-alanine is the simplest chiral amino acid. Its side chain is a single methyl group on the α-carbon. Its SMILES is C[C@@H](C(=O)O)N.

### Is alanine chiral?

Yes. Its α-carbon carries four different groups (H, CH₃, NH₂, COOH). Natural L-alanine is the (S) enantiomer.

### Is alanine polar or non-polar?

Its side chain (CH₃) is classed as non-polar, but the whole molecule is a polar zwitterion.

### What is the chemical formula and molar mass of Alanine?

Alanine is C3H7NO2 with a molar mass of 89.09 g/mol. It contains 13 atoms: 3 carbon, 7 hydrogen, 1 nitrogen, 2 oxygen.

### What is the IUPAC name of Alanine?

The IUPAC name is (2S)-2-aminopropanoic acid.

### How do I draw Alanine?

Open the MolDraw editor, paste the SMILES C[C@@H](C(=O)O)N or type "Alanine" in name search, and the structure is drawn for you. You can then export it as PNG, SVG, MOL or CDXML.

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