Map object's certain attibutes as key value pair

I have an object as follows:

{
  id: "72232915",
  entryCode: "999",
  conjunction1: "1234567",
  conjunction2: "8910111",
  conjunction3: "1314151",
  date: "08/02/2017"
}

I want to tranform the object into the following format:

{
  id: "72232915",
  entryCode: "999",
  conjunctions: {
                  1: "1234567"       
                  2: "8910111"
                  3: "1314151"
               },
  date: "08/02/2017"
}

Any ideas of how I can achieve the desired output?

Here is Typescript code that does it (very specific to what you are asking):

let o = {
  id: "72232915",
  entryCode: "999",
  conjunction1: "1234567",
  conjunction2: "8910111",
  conjunction3: "1314151",
  date: "08/02/2017"
};

const conjunctions = {};

for (const prop in o) {
  const regex = /^conjunction(.+)$/;
  const matches = prop.match(regex);

  if (matches?.length === 2) {
    const conjunction = matches[1];

    conjunctions[conjunction] = o[prop];
    delete o[prop];
  }
}

o = Object.assign({}, o, {conjunctions});
console.log(o);