Convert `D`-glucopyranose to `2,3,4-` triethyl gluocopynoside.

Explanation

To convert D-glucopyranose to 2,3,4-triethylglucopyranoside, we will follow a series of chemical reactions. Here’s a step-by-step breakdown of the process:

### Step 1: Structure of D-glucopyranose
- **D-glucopyranose** is a six-membered cyclic form of glucose. It contains five hydroxyl (–OH) groups and one aldehyde group. The structure can be represented as follows:

```
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/ \
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