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# Create AaMonomer

POST https://{tenant_name}.benchling.com/api/v3/aa-monomer
Content-Type: application/json

Create AaMonomer.

Reference: https://docs.benchling.com/docs/api/benchling-api/aa-monomer/create

## Authentication

- `Authorization` header (bearer token, required) — Bearer authentication of the form `Bearer <token>`, where token is your auth token.

## Request

### Headers

- `EARLY-ACCESS` (string, optional) — Set to true to access beta operations via /api/v3.

### Body (application/json)

This endpoint expects a CreateAaMonomerInput.

- `chemicalStructure` (AaMonomerChemicalStructureInput, required)
- `name` (string, required)
- `naturalAnalog` (enum, required) — The standard amino acid single-letter code that this monomer is an analog of.
  - Allowed values: `A`, `B`, `C`, `D`, `E`, `F`, `G`, `H`, `I`, `J`, `K`, `L`, `M`, `N`, `O`, `P`, `Q`, `R`, `S`, `T`, `U`, `V`, `W`, `X`, `Y`, `Z`
- `symbol` (string, required) — User-defined identifier of the monomer, unique per tenant.
- `customMolecularWeight` (double, optional) — Optional molecular weight value that the user can provide to override the calculated value.

## Response

### 201

Created

- `__typename` (string, optional)
- `archiveReason` (string, optional, nullable)
- `archived` (boolean, optional)
- `attachmentPoints` (list of enum, optional) — The capping groups present at each attachment point where the monomer bonds to other monomers.
  - Allowed values: `H`, `OH`, `NH2`, `CH3`
- `calculatedMolecularWeight` (double, optional) — The molecular weight of the monomer with capping groups removed, computed using the average atomic weights of each element weighted by natural isotopic frequency.
- `canonicalSmiles` (string, optional) — The SMILES representation of the chemical structure after being standardized.
- `createdAt` (string, optional)
- `creator` (PrincipalRef, optional, nullable)
- `customMolecularWeight` (double, optional, nullable) — Optional molecular weight value that the user can provide to override the calculated value.
- `exactMolecularWeight` (double, optional) — The exact (monoisotopic) molecular weight of the monomer with capping groups removed, computed using the atomic weight of the most frequent isotope of each element.
- `id` (string, optional)
- `isNatural` (boolean, optional) — Whether this monomer represents a natural (unmodified) amino acid, as opposed to a modified or synthetic variant.
- `modifiedAt` (string, optional)
- `molfile` (string, optional) — The molfile representation of the chemical structure.
- `name` (string, optional)
- `naturalAnalog` (enum, optional) — The standard amino acid single-letter code that this monomer is an analog of.
  - Allowed values: `A`, `B`, `C`, `D`, `E`, `F`, `G`, `H`, `I`, `J`, `K`, `L`, `M`, `N`, `O`, `P`, `Q`, `R`, `S`, `T`, `U`, `V`, `W`, `X`, `Y`, `Z`
- `originalSmiles` (string, optional, nullable) — The SMILES string that was originally provided upon creation. Null if the user did not originally provide SMILES.
- `symbol` (string, optional) — User-defined identifier of the monomer, unique per tenant.

## Errors

### 400 Aa Monomer Create Request Bad Request Error

Bad Request

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 403 Aa Monomer Create Request Forbidden Error

Forbidden

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 404 Aa Monomer Create Request Not Found Error

Not Found

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 409 Aa Monomer Create Request Conflict Error

Conflict

- `detail` (GeneralErrorDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)

### 429 Aa Monomer Create Request Too Many Requests Error

Too Many Requests

- `detail` (TooManyRequestsErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `invalidId` (string, optional)
- `violated-policies` (list of enum, optional) — The budget policies that rejected the request, in canonical order: `user`, `integration`, then `tenant`.
  - Allowed values: `user`, `integration`, `tenant`

### 500 Aa Monomer Create Request Internal Server Error

Internal Server Error

- `detail` (InternalServerErrorBodyDetail, required, nullable)
- `instance` (string, required)
- `status` (integer, required)
- `title` (string, required, nullable)
- `type` (string, required)
- `errorId` (string, optional)

## Types

### AaMonomerChemicalStructureInput

- `structureFormat` (enum, required)
  - Allowed values: `smiles`
- `value` (string, required)

### PrincipalRef

- `__typename` (string, optional)
- `id` (string, optional)

### GeneralErrorDetail

### TooManyRequestsErrorBodyDetail

### InternalServerErrorBodyDetail

## Examples

**Request**

```json
{
  "chemicalStructure": {
    "structureFormat": "smiles",
    "value": "value"
  },
  "name": "name",
  "naturalAnalog": "A",
  "symbol": "symbol"
}
```

**Response**

```json
{
  "__typename": "__typename",
  "archiveReason": "archiveReason",
  "archived": true,
  "attachmentPoints": [
    "H"
  ],
  "calculatedMolecularWeight": 1.1,
  "canonicalSmiles": "canonicalSmiles",
  "createdAt": "createdAt",
  "creator": {
    "__typename": "__typename",
    "id": "id"
  },
  "customMolecularWeight": 1.1,
  "exactMolecularWeight": 1.1,
  "id": "id",
  "isNatural": true,
  "modifiedAt": "modifiedAt",
  "molfile": "molfile",
  "name": "name",
  "naturalAnalog": "A",
  "originalSmiles": "originalSmiles",
  "symbol": "symbol"
}
```

**SDK Code**

```python
import requests

url = "https://{tenant_name}.benchling.com/api/v3/aa-monomer"

payload = {
    "chemicalStructure": {
        "structureFormat": "smiles",
        "value": "value"
    },
    "name": "name",
    "naturalAnalog": "A",
    "symbol": "symbol"
}
headers = {
    "Authorization": "Bearer <token>",
    "Content-Type": "application/json"
}

response = requests.post(url, json=payload, headers=headers)

print(response.json())
```

```javascript
const url = 'https://{tenant_name}.benchling.com/api/v3/aa-monomer';
const options = {
  method: 'POST',
  headers: {Authorization: 'Bearer <token>', 'Content-Type': 'application/json'},
  body: '{"chemicalStructure":{"structureFormat":"smiles","value":"value"},"name":"name","naturalAnalog":"A","symbol":"symbol"}'
};

try {
  const response = await fetch(url, options);
  const data = await response.json();
  console.log(data);
} catch (error) {
  console.error(error);
}
```