Problem beim Installieren des Web3-Moduls. Ubuntu

Es funktioniert einfach nicht. Ich habe stundenlang im Internet gesucht und keine Lösung scheint für mich zu funktionieren.

root@ewerton-azevedo-blockchainlab-5299615:/home/ubuntu/workspace# npm 
install ethereumjs-testrpc web3

> uglifyjs-webpack-plugin@0.4.6 postinstall 
/home/ubuntu/workspace/node_modules/uglifyjs-webpack-plugin
> node lib/post_install.js

sh: 1: node: Permission denied
npm WARN enoent ENOENT: no such file or directory, open 
'/home/ubuntu/workspace/package.json'
npm WARN workspace No description
npm WARN workspace No repository field.
npm WARN workspace No README data
npm WARN workspace No license field.
npm WARN optional SKIPPING OPTIONAL DEPENDENCY: fsevents@1.1.2 
(node_modules/fsevents):
npm WARN notsup SKIPPING OPTIONAL DEPENDENCY: Unsupported platform f or  
fsevents@1.1.2: wanted {"os":"darwin","arch":"any"} (current: 
{"os":"linux","arch":"x64"})

npm ERR! file sh
npm ERR! code ELIFECYCLE
npm ERR! errno ENOENT
npm ERR! syscall spawn
npm ERR! uglifyjs-webpack-plugin@0.4.6 postinstall: `node  
lib/post_install.js`
npm ERR! spawn ENOENT
npm ERR! 
npm ERR! Failed at the uglifyjs-webpack-plugin@0.4.6 postinstall script.
npm ERR! This is probably not a problem with npm. There is likely additional 
logging output above.

npm ERR! A complete log of this run can be found in:
npm ERR!     /root/.npm/_logs/2017-08-30T13_55_41_153Z-debug.log