--- title: "How to Manage Your Organisation's Cap Groups" slug: "how-to-manage-your-organisations-cap-groups" status: "new" updated: 2026-11-04T11:59:45Z published: 2026-11-04T11:59:45Z canonical: "docs.discngine.com/how-to-manage-your-organisations-cap-groups" --- > ## Documentation Index > Fetch the complete documentation index at: https://docs.discngine.com/llms.txt > Use this file to discover all available pages before exploring further. # How to Manage Your Organisation's Cap Groups This guide shows how to add a cap group your chemistry needs, and retire a cap group you no longer want offered. For what a cap group is and why the choice matters, see [Attachment Points and CAP Groups](/public/docs/attachment-points-and-cap-groups). **Prerequisites**: the **Administrator** role in Biotoolkit Monomers. The **Cap groups** entry appears in the navigation menu, under **Administration**, only for Administrators. ## Step 1: Open the Cap groups page In the navigation menu, open **Administration** and click **Cap groups**. The page lists every cap group your organisation can use: - the **Public** ones, shipped with Biotoolkit and read-only, marked *System* in the **By** column; - your organisation's **Private** ones, with the account that last changed them. The **Scope** chips (**All**, **Private**, **Public**) and **Status** chips (**All**, **Active**, **Inactive**) narrow the list, and the search box finds a symbol or a name. ![The Cap groups page: the five public cap groups, then the organisation's private ones, Br, Cl, I and the new Propynyl, with the Scope and Status chips above the report](https://cdn.document360.io/dde9293e-c107-4b3e-9774-9c9c296ed970/Images/Documentation/biotoolkit-monomer-service-cap-groups(3).png?sv=2026-02-06&spr=https&st=2026-11-11T08%3A23%3A55Z&se=2026-11-11T09%3A23%3A55Z&sr=c&sp=r&sig=1r5QX3WIUjc5az2yqm90VIHvSPRUW3hZEN7GG8To66U%3D) Your private cap groups are visible to your organisation only. Another organisation never sees them, and cannot use them in its monomers or imports. ## Step 2: Add a cap group Click **New cap group** and fill in the dialog: | Field | What to enter | | --- | --- | | **Symbol** | The name curators choose in the monomer form and write in import files, such as `Propynyl`. At most 50 characters, without a comma, a semicolon or a colon (an import file reads `R1:Propynyl`). It must not already be one of your organisation's cap groups, nor a public one such as `OH`, in any case. | | **Name** | The readable name shown next to the symbol, such as `Propargyl`. | | **SMILES template** | The cap's structure, with its attachment point written `[*:{n}]`, exactly once, and no space. `{n}` becomes the R-group number when the cap is applied. | | **Description** | Optional: when to use this cap. | | **Display order** | Optional: the cap's position in the monomer form's selector. Without one, it comes after the ordered caps. | | **Active** | On: the cap is offered at once. | As you type the template, the preview draws the cap on `R1` and checks it. **Valid structure, one attachment point** means the template is ready; otherwise the preview names the problem, such as a template with no attachment point or with two. ![The New cap group dialog for Propynyl: symbol, name Propargyl, a propargyl template drawn on R1 with "Valid structure, one attachment point", a description, and the Active switch on](https://cdn.document360.io/dde9293e-c107-4b3e-9774-9c9c296ed970/Images/Documentation/biotoolkit-monomer-service-cap-group-new(3).png?sv=2026-02-06&spr=https&st=2026-11-11T08%3A23%3A55Z&se=2026-11-11T09%3A23%3A55Z&sr=c&sp=r&sig=1r5QX3WIUjc5az2yqm90VIHvSPRUW3hZEN7GG8To66U%3D) Click **Create**. The cap group is listed as **Private** and **Active**. Curators of your organisation can choose it at once for an R-group on the monomer form, and write it in an import file as `R1:Propynyl`. The Biotoolkit services that compute structures from your monomers pick it up within a minute. The symbol cannot be changed afterwards: monomers and import files refer to the cap by it. To use another symbol, add a new cap group and retire the old one. A public cap group cannot be replaced. To cap with another structure than a public cap gives, add a cap group with a symbol of its own, such as `OMe` rather than a second `OH`: public monomers name their caps by symbol, so a private `OH` would change their structure for your organisation. Click the symbol of a public cap group to read its template and the number of your organisation's monomers that use it. ## Step 3: Change or retire a cap group Click the symbol of one of your private cap groups, or its pencil in the **Actions** column, to open it. You can change everything except the symbol, then click **Save changes**. To stop offering a cap group, switch **Active** off and click **Save changes**. The cap leaves the monomer form's selector, and an import that names it is refused. Monomers that already use it keep their structure, and you can switch it back on at any time. ## Step 4: Delete a cap group nobody uses The dialog of a private cap group says how many of your organisation's monomers use it. - **No monomer of your tenant uses this cap.** The **Delete** button is available. Click it and confirm. An import that names the symbol is then refused. - **One or more monomers use it.** The dialog offers no **Delete**, and says *A cap in use cannot be deleted: deactivate it to retire it*. Switch **Active** off instead, as in step 3. A cap group in use cannot be deleted because its monomers would keep naming a cap group that no longer exists. Worse, a cap group added later under the same symbol, with another template, would silently give those monomers' caps another structure. Deactivating avoids both, and stays reversible. ## Related - [Attachment Points and CAP Groups](/public/docs/attachment-points-and-cap-groups): what a cap group is, and why the choice matters. - [How to Create or Edit a Monomer](/public/docs/how-to-create-or-edit-a-monomer): where curators choose a cap group for each R-group. - [How to Import Monomers in Bulk](/public/docs/how-to-import-monomers-in-bulk): how cap groups are written in an import file.